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BMC 1.5 spill rail - flexi return pipe


StephenA
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Yes, the last link is for a double banjo on the top or rear side, (No idea why mine was on the side), as it would vent the CAV better on the top. The part I did not find was the final screw in one way fitting for the CAV 296, although it's unlikely it would be where the rail failed due to fatigue.

 

This is similar to the fuel hose I purchased from Hyperhose, a local special fuel related parts specialist, BUT a word of warning, make sure the actual nitrile or rubber is thick enough, as some cheap thin walled versions do fail under pressure:

Stainless Steel Braided Nitrile Rubber Fuel Hose Line Diesel Petrol Hose Car Van | eBay

Edited by TNLI
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27 minutes ago, TNLI said:

Yes, the last link is for a double banjo on the top or rear side, (No idea why mine was on the side), as it would vent the CAV better on the top. The part I did not find was the final screw in one way fitting for the CAV 296, although it's unlikely it would be where the rail failed due to fatigue.

 

This is similar to the fuel hose I purchased from Hyperhose, a local special fuel related parts specialist, BUT a word of warning, make sure the actual nitrile or rubber is thick enough, as some cheap thin walled versions do fail under pressure:

Stainless Steel Braided Nitrile Rubber Fuel Hose Line Diesel Petrol Hose Car Van | eBay

 

No - not a double push fit banjo - ours, and I've seen others, is either a rigid pipe (or flex pipe fitting ) on one side and a male thread on the other side which the armoured fuel return to the tank connects to.

 

Anyway we got ours rebuilt with the male thread still there. I think its metal between the injectors then a BS marked flexi hose from the final injector back down the banjo on the top of the CAV. If I remember I'll take a photo in a week and a half when I'm on the boat.

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One word of warning if you are replacing an old CAV 296 truck primary fuel filter with a new shiny modern spin on job that has the same 4 fuel line connections, be careful as the unit I purchased on Fleabay has the 4 ports numbered and labelled in reverse order. That will result in you connecting it the wrong way round to the HP pump. So no 1 and no2 are in reverse order, with the no 3 outlet on the front of the new units head. not check if the same applies to ports 1 and 2 yet.

 

The other non standard item in primary fuel filter plumbing terms is that the original CAV filter had the spill rail connected to the outlet port no 2 on the far side with a 2 way banjo fitting and longer vented bolt fitting. I tried to connect the first part of my spill rail to the top, BUT I can't find the correct bolt to fit it, although it could well be in my old parts bin.

I made up 2 new Copper pipes, (No BS mark), for the HP pump feed and return lines, but luckily they are the same length, cos I've run out of nipples.

 

PS: Has anyone actually failed a BS or insurance inspection because there is no mark on their stainless braided fuel lines ?? If they have, can they please scan and post the failure notice.

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4 hours ago, TNLI said:

One word of warning if you are replacing an old CAV 296 truck primary fuel filter with a new shiny modern spin on job that has the same 4 fuel line connections, be careful as the unit I purchased on Fleabay has the 4 ports numbered and labelled in reverse order. That will result in you connecting it the wrong way round to the HP pump. So no 1 and no2 are in reverse order, with the no 3 outlet on the front of the new units head. not check if the same applies to ports 1 and 2 yet.

 

The other non standard item in primary fuel filter plumbing terms is that the original CAV filter had the spill rail connected to the outlet port no 2 on the far side with a 2 way banjo fitting and longer vented bolt fitting. I tried to connect the first part of my spill rail to the top, BUT I can't find the correct bolt to fit it, although it could well be in my old parts bin.

I made up 2 new Copper pipes, (No BS mark), for the HP pump feed and return lines, but luckily they are the same length, cos I've run out of nipples.

 

PS: Has anyone actually failed a BS or insurance inspection because there is no mark on their stainless braided fuel lines ?? If they have, can they please scan and post the failure notice.

 

But I'm not, but we didn't

 

And yes we have failed for having inadequately labelled fuel lines - an no we can't because we don't keep stuff like that.

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I really can't understand why my old donkey had a CAV 296 with a very different set of fuel lines and connections to those clearly shown in the operators handbook. The big difference is the complete lack of a fuel return line, as the spill off rail is connected to the top of the filter housing vent nut, and the return port is blanked off. 

Does anyone with a BMC 1500 have their 296 connected in the manner approved of by Mr Morris ??

 

I've been looking at the connections I have from the old 296 unit that is now for sale in Fleabay, and it appears that the return port on the far side, (No 3 or 4), was simply used to support the injectors return fuel line, as the banjo hole was in the wrong place to have vented air from the filter or fuel lines. The hole was too far below the top, so it could not vent anything, it was just supporting the return line fittings. 

So who has a donkey that runs well and is not a PITA to bleed after filter changes, that lacks a real return to tank line ??

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Daarn it, I did not see this item when ordering parts to make a new fuel rail, seriously miffed as I know how to solder Copper and I've got plenty of Copper pipe in the  bin:

M8 Metric Steel Double Banjo to Solder for 5 mm Pipe Fuel and Oil Lines - NEW | eBay

 

End of rail fitting:

M8 8mm BANJO TO 5mm SOLDER PIPE Too, for FUEL & OIL unplated STEEL | eBay

 

Note: The reason these are cheap fittings is that they are un plated steel, so should be painted after the rail is finished.

 

Edited by TNLI
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22 minutes ago, TNLI said:

Note: The reason these are cheap fittings is that they are un plated steel, so should be painted after the rail is finished.

 

 

As are all the 1.5 and 1.8 banjo unions and bolts that I have come across, probably hundreds, if not thousands.

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5 hours ago, TNLI said:

I really can't understand why my old donkey had a CAV 296 with a very different set of fuel lines and connections to those clearly shown in the operators handbook. The big difference is the complete lack of a fuel return line, as the spill off rail is connected to the top of the filter housing vent nut, and the return port is blanked off. 

Does anyone with a BMC 1500 have their 296 connected in the manner approved of by Mr Morris ??

 

Not sure who this Mr Morris is that you keep talking about but I have had a whole fleet of BMC 1.5s running perfectly while piped up as per BMC and CAV recommendations. As I have said before you seem to have a "bitza" engine so unless you post an image of what you are talking about I and I doubt many others, can't know.

 

The CAV filter head normally has FOUR ports, two in each side. All have arrows on them indicating direction of fuel flow but only two are used and two are blanked off. This is to ensure it is  easy to connect the pipework whatever engine or side of the engine it is fitted to.

 

Any air gathering in the filter head will be right at the top so this is vented via a banjo bolt fitted into the top of the filter head. Normally this banjo and bolt is significantly larger than the ones for the injector leak off but if the engine is very old or had a filter form another application fitted this might not be true. In that case it may use a double length banjo bolt the same diameter as the injector ones. This bolt will normally have two hole in its side. The large bolt has one hole, in the correct vertical position.

 

The problems you seem to be having with this seem to relate to non-standard parts. I have come across a number of home made banjo bolts and they may have the holes, if any, in the wrong place. A photo will help explain your problem.

 

By the way, if you ever think you many need to pass a BSS examination on no account soft solder any fuel connections. The BSS requires silver solder or braze, but brazing gets the banjo a bit too close to the temperature at which it falls apart (un-brazes its stub pipes) so silver soldering is a bit easier.

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42 minutes ago, Tony Brooks said:

 

Not sure who this Mr Morris is that you keep talking about but I have had a whole fleet of BMC 1.5s running perfectly while piped up as per BMC and CAV recommendations. As I have said before you seem to have a "bitza" engine so unless you post an image of what you are talking about I and I doubt many others, can't know.

 

The CAV filter head normally has FOUR ports, two in each side. All have arrows on them indicating direction of fuel flow but only two are used and two are blanked off. This is to ensure it is  easy to connect the pipework whatever engine or side of the engine it is fitted to.

 

Any air gathering in the filter head will be right at the top so this is vented via a banjo bolt fitted into the top of the filter head. Normally this banjo and bolt is significantly larger than the ones for the injector leak off but if the engine is very old or had a filter form another application fitted this might not be true. In that case it may use a double length banjo bolt the same diameter as the injector ones. This bolt will normally have two hole in its side. The large bolt has one hole, in the correct vertical position.

 

The problems you seem to be having with this seem to relate to non-standard parts. I have come across a number of home made banjo bolts and they may have the holes, if any, in the wrong place. A photo will help explain your problem.

 

By the way, if you ever think you many need to pass a BSS examination on no account soft solder any fuel connections. The BSS requires silver solder or braze, but brazing gets the banjo a bit too close to the temperature at which it falls apart (un-brazes its stub pipes) so silver soldering is a bit easier.

 

Thanks for the reply and the top of my spin on conversion is labelled exactly as per the original 296 filter head, (But in reverse). Lots of marine BMC conversions are almost home brews, but I'm trying to do my best to copy the OEM spec diagrams, so there are 2 fuel lines from filter top to the HP pump, and only one to the lift pump and tank, (mine had 2). So only one port is going to be blanked off on the far side, as per the operators manual.

 

One swift question I have is about the very top of the heat exchanger cover, (mine is the keel cooled version), as it has an unused mounting plate that is part of the cover and looks OEM, except it's not as none of the vid clips or manuals shows it. this mounting plate position is located just in front of the exhaust flange bolts and has 2 5mm holes for some type of bracket or add on. Anyone know what was supposed to be fitted on top of it ?? 

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15 minutes ago, TNLI said:

 

Thanks for the reply and the top of my spin on conversion is labelled exactly as per the original 296 filter head, (But in reverse). Lots of marine BMC conversions are almost home brews, but I'm trying to do my best to copy the OEM spec diagrams, so there are 2 fuel lines from filter top to the HP pump, and only one to the lift pump and tank, (mine had 2). So only one port is going to be blanked off on the far side, as per the operators manual.

 

One swift question I have is about the very top of the heat exchanger cover, (mine is the keel cooled version), as it has an unused mounting plate that is part of the cover and looks OEM, except it's not as none of the vid clips or manuals shows it. this mounting plate position is located just in front of the exhaust flange bolts and has 2 5mm holes for some type of bracket or add on. Anyone know what was supposed to be fitted on top of it ?? 

 

Yes, I was  incorrect, only one port in the filter head is blanked as you say, that is correct.

 

If your engine is keel cooled than it does not have a heat exhanger for the coolant. It will have a water jacket manifold cum header tank. I am also about 99% sure it is not an OEM manifold as per the official BMC marinisations. (Tempest or Newage). For an engine of the age that uses your form of flywheel housing cum engine feet casting the manifold was very different and if there was a heat exchanger it was mounted across the front of the engine. Once again a photo of what you are trying to describe would help but I can't think of anything that would need a bracket in the position I think you are describing.

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2 hours ago, Tony Brooks said:

 

Yes, I was  incorrect, only one port in the filter head is blanked as you say, that is correct.

 

If your engine is keel cooled than it does not have a heat exhanger for the coolant. It will have a water jacket manifold cum header tank. I am also about 99% sure it is not an OEM manifold as per the official BMC marinisations. (Tempest or Newage). For an engine of the age that uses your form of flywheel housing cum engine feet casting the manifold was very different and if there was a heat exchanger it was mounted across the front of the engine. Once again a photo of what you are trying to describe would help but I can't think of anything that would need a bracket in the position I think you are describing.

Thanks for the reply and there was no mark on the sort of backing plate with 2 threaded holes, so no heat exchanger was fitted, or it was removed in the past 60 years or so. ASAP do make a few odd heat exchangers that could be fitted like the one for the gearbox.

 

One more rather off topic question is about the way the inlet and outlets from the block for the cooling system. I have the normal internal circulating pump inlet and another normal outlet from the top above the gearbox, BUT there is a 3/4 inch barbed brass pipe fitting near the new shiny rocker cover that is normally for hot water, so the question is, where is the inlet for the hot water supposed to be ?? It might be the 10mm or so bolt has blanked at the other outside edge of the cover ??

 

I hope to be able to post a picture or clip after my sister visits today, assuming she is willing to spend a few minutes in an unheated garage.

 

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23 minutes ago, TNLI said:

Thanks for the reply and there was no mark on the sort of backing plate with 2 threaded holes, so no heat exchanger was fitted, or it was removed in the past 60 years or so. ASAP do make a few odd heat exchangers that could be fitted like the one for the gearbox.

 

One more rather off topic question is about the way the inlet and outlets from the block for the cooling system. I have the normal internal circulating pump inlet and another normal outlet from the top above the gearbox, BUT there is a 3/4 inch barbed brass pipe fitting near the new shiny rocker cover that is normally for hot water, so the question is, where is the inlet for the hot water supposed to be ?? It might be the 10mm or so bolt has blanked at the other outside edge of the cover ??

 

I hope to be able to post a picture or clip after my sister visits today, assuming she is willing to spend a few minutes in an unheated garage.

 

 

As you say for a keel cooled boat the coolant return inlet is the one on the engine  water pump of 1"+ diameter.

 

The marine engines have a different thermostat housing with the outlet pointing at the manifold but from memory yours looks like the automotive one so points in more or less the opposite way. However there is no reason you can't make up a pipe or hoses to take the outlet flow to the correct place. It will need to be no smaller than the spigot on the water pump.

 

Normally that outlet would run to on large connector on the manifold and another large connector, often at the other bend, would be the skin tank/keel cooler connection. All in large bore hoses and pipes. So I would expect this: Engine thermostat housing outlet > manifold/header tank > skin tank/keel cooler > gear box oil cooler if fitted > water pump inlet. This is for a dry exhaust boat.

 

The barbed connection on the top and at the back (or front) of the head by the rocker cover is the out connection to the calorifier coil. The calorifier return is T'd into the pipe or hose that feeds into the water pump. It could be anywhere between the gearbox oil cooler (if fitted) and the engine water pump inlet.

 

I need to see the top,  bottom, side and the ends of your manifold to say much more. I need to see where, if at all, the large bore connections are in it. I suspect there may only be small bore connections for direct raw water cooling but don't know. We are back to the start of all this when I asked for photos so we can see exactly what you have bought.

 

 

 

 

 

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Thanks Tony and my brother in law took some pic's today. Now before all the nay sayers start on about the Ferrari Red, or incorrect HP fuel lines etc. I have not finished rebuilding this partial rebuild of a keel cooled BMC 1500. I have not for example connected up the 2 HP pump Copper pipes I made up yesterday and just shoved them in so the pics look sort of complete. The reason I'm posting 6 is so Tony can comment on what the odd 2 hole backing plate that is on the top of the heat exchanger cover is for, as it was not in use for anything. I might decide to use it for a mounting bracket for an auto burst fire bottle etc. That odd extra is alongside the outlet port or inlet port for what I thought might be a missing hot water system. Although I can't figure out how an additional heat exchanger was plumbed in, as there is only one port visible.

 

As stated in a previous post the original oil and fuel filter units were both replaced with spin on conversion kits with Bosch or Mann filters and all new fuel lines. The air filter unit is an OEM washable, so it was just cleaned and painted with varnish. When I fish off the engine, it will be moved first to a local company for a full crank shaft alignment and shaft inspection. Not touched the gearbox so far, as it seems OK, but will install an additional sump magnet some time.

 

Last comment for the nay sayers, I'm not painting it British Leyland Green, cos I plan to fit lights in the engine bay, and red is a far better colour for the eyes at night, also my young daughter likes Ferrari's, so Ferrari or Signal red it will be.

BMC1(Finger).jpg

BMC(Air filter).jpg

BMC2(Gearbox).jpg

BMC3(Exhaust).jpg

BMC5.jpg

BMC6(Fitting).jpg

Edited by TNLI
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Thanks. It is all clear now.

 

First that little oval at the back of the manifold cover. I think it allows you to fit the feed to the exhaust elbow on a wet exhaust boat. They would drill the cover and then bolt on an outlet adapter. You can see a similar but larger oval under the filler. That would give the option to leave  that one un-drilled for a raw  water cooled wet exhaust that would not need a filler there.

 

I think the rectangular blanking plate on the front of the manifold is an alternative position for the exhaust elbow that  could be used in conjunction with a V drive.

 

Yes, I remembered wrong, it is  a marine thermostat housing and it is properly connected.  The red pipe out the back of the manifold is the hot water out to the skin tank/keel cooler. Don't be tempted to plumb that into the oil cooler because it would become an oil  warmer as it would be in the hot "out of engine" flow. I understand Beta did something similar with not very happy  results.

 

The skin tank outlet hose goes to the oil cooler and then on to the water pump inlet.

 

FWIW typically the bracket to hold the fuel filter would be the other way up with the filter mounted lower down. That way if you  find the bracket is a bit flimsy so it vibrates you can wedge a piece of wood between it and the head/block.

 

I can now see that the filter you have seems to have a non-standard (for BMCs) banjo bolt thread. It looks as if it uses the same sized banjo and bolt as the injector leak off connection, but please check the diameter and thread carefully. I suspect a double length bolt and two banjos. One from the injectors and the other back to the tank. I think any half decent diesel injection specialist should stock the parts. Check out Poole Diesels

 

 

The engine is looking good and far better now.

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23 minutes ago, Tony Brooks said:

Thanks. It is all clear now.

 

First that little oval at the back of the manifold cover. I think it allows you to fit the feed to the exhaust elbow on a wet exhaust boat. They would drill the cover and then bolt on an outlet adapter. You can see a similar but larger oval under the filler. That would give the option to leave  that one un-drilled for a raw  water cooled wet exhaust that would not need a filler there.

 

I think the rectangular blanking plate on the front of the manifold is an alternative position for the exhaust elbow that  could be used in conjunction with a V drive.

 

Yes, I remembered wrong, it is  a marine thermostat housing and it is properly connected.  The red pipe out the back of the manifold is the hot water out to the skin tank/keel cooler. Don't be tempted to plumb that into the oil cooler because it would become an oil  warmer as it would be in the hot "out of engine" flow. I understand Beta did something similar with not very happy  results.

 

The skin tank outlet hose goes to the oil cooler and then on to the water pump inlet.

 

FWIW typically the bracket to hold the fuel filter would be the other way up with the filter mounted lower down. That way if you  find the bracket is a bit flimsy so it vibrates you can wedge a piece of wood between it and the head/block.

 

I can now see that the filter you have seems to have a non-standard (for BMCs) banjo bolt thread. It looks as if it uses the same sized banjo and bolt as the injector leak off connection, but please check the diameter and thread carefully. I suspect a double length bolt and two banjos. One from the injectors and the other back to the tank. I think any half decent diesel injection specialist should stock the parts. Check out Poole Diesels

 

 

The engine is looking good and far better now.

 

Thanks Tony and the new spin on fuel filter head is mounted on the same steel plate as the original, there is no way it could vibrate and cause an issue. I've kept the original banjo fittings and they do fit the new filter unit apart from the odd spill rail that was not fitted to the top correctly, so is too big. Easy to find all the different fittings from various companies using Fleabay or Amazinzone. 

  I know from previous comments how to design and build a keel cooling system and that the main outlet pipe connects to the hull cooling tank, or alloy radiator. I've already purchased a new nice shiny alloy header tank, as the original was missing, and I don't like plastic header tanks anyway. Still early days in terms of the cooling system and possible hot water system.

 

So, the important part is that you think the barbed brass 3/4 inch hose fitting opposite the strange oval support or backing plate was no used because there was no sign of another inlet one, or is it part of a marine thermostat unit ?? Can't think it is, as that oval plate can't be removed without to change a secondary thermostat ??

 

PS: I will try the bracket for the fuel filter unit the other way up to see if it makes more room for the stop cable or hoses etc.

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16 minutes ago, TNLI said:

So, the important part is that you think the barbed brass 3/4 inch hose fitting opposite the strange oval support or backing plate was no used because there was no sign of another inlet one, or is it part of a marine thermostat unit ?? Can't think it is, as that oval plate can't be removed without to change a secondary thermostat ??

 

As I said this morning, it is the feed for a calorifier coil with the return into the pipe running into the engine water pump.

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1 hour ago, Tony Brooks said:

 

As I said this morning, it is the feed for a calorifier coil with the return into the pipe running into the engine water pump.

OK, so that means that outlet could be connected to a hot water heat exchanger some place convenient, and that the outlet pipe from that heat exchanger is then joined to the hose leading back to the circulating pump inlet from the cooling tank or radiator ??

 

I just spent around 10 mins fitting the spin on fuel filter unit bracket the correct way up, or rather down as you suggested. Definitely better in terms of not wasting space.

 

PS: This might be the missing cooling system pipe for an add on coil or heat exchanger, although it seems to need metal joiners to allow the rest of the coolant hoses to be fitted to it: 

Silicone Hose with Calorifier Take Off (asap-supplies.com)

Edited by TNLI
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7 minutes ago, TNLI said:

OK, so that means that outlet could be connected to a hot water heat exchanger some place convenient, and that the outlet pipe from that heat exchanger is then joined to the hose leading back to the circulating pump inlet from the cooling tank or radiator ??

 

I just spent around 10 mins fitting the spin on fuel filter unit bracket the correct way up, or rather down as you suggested. Definitely better in terms of not wasting space.

 

Yes, you have it.

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41 minutes ago, Tony Brooks said:

 

Yes, you have it.

Thanks Tony, and I've just been out looking at the bracket for the spin on filter again, and luckily there is room below the unit to remove the spin on filter, AND still have room for a small bowl under it to catch any spilt diesel. I always try do any routine service items like filter and oil changes whilst at sea, that means getting used to removing spin on filters whilst the boat is rolling around and not making a right mess of the engine. 

  One reason I've replaced the old CAV 296 fuel filter and the canister type oil filter for all new spin on conversion kits is that it is almost impossible to change that type of filter with one hand. You might ask why you need to be able to do such a task using only one hand, and the old salty dog seafarers saying, "One hand for the boat and the other for yer old donkey"!

Edited by TNLI
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