BMC 1.5 timing marks

[p6rob]

Well, the weekend was a disaster as far as getting the engine to run was concerned.

I'm struggling to work out where TDC is on the engine as there appears to be two pairs of factory marked notches on the front pulley and no timing bracket to align them to.

Is there a foolproof method to figure out TDC without taking the front pulley and timing cover off so I can check and set the injector pump timing.

 

Thanks for any help

 

There are so many unknowns about this engine. I bought the boat about three weeks ago. The engine had been reconditioned last May, but because someone, either the reconditioners or boatyard, tore the sump while fitting the drain pump, it had been left unfinished.

I'm pretty certain the problem is injector timing as, with squirts of easy start, the engine would attempt to run. I filled the filters with fresh fuel and bled everything through and saw fuel running down the injector pipes.

[RLWP]

Taking the rocker cover off is one way. To get it roughly right, and work out which notch you are working with, TDC occurs when the exhaust valve is closing and the inlet opening. So watch the pair of rockers on cylinder four and when they are both rocking cylinder one will be around TDC. You should now be able to identify the correct notch on the pulley and set it correctly

 

Richard

 

MORE: is your sump drain pump on the end of a rigid copper pipe? Ours was, and eventually with it vibrating around it tore the drain out of the sump

Edited March 18, 2013 by RLWP

[Tony Brooks]

Well, the weekend was a disaster as far as getting the engine to run was concerned.

I'm struggling to work out where TDC is on the engine as there appears to be two pairs of factory marked notches on the front pulley and no timing bracket to align them to.

Is there a foolproof method to figure out TDC without taking the front pulley and timing cover off so I can check and set the injector pump timing.

 

Thanks for any help

 

There are so many unknowns about this engine. I bought the boat about three weeks ago. The engine had been reconditioned last May, but because someone, either the reconditioners or boatyard, tore the sump while fitting the drain pump, it had been left unfinished.

I'm pretty certain the problem is injector timing as, with squirts of easy start, the engine would attempt to run. I filled the filters with fresh fuel and bled everything through and saw fuel running down the injector pipes.

 

 

Simply timing the 1.5 injector pump does not require any timing marks on the front pully or flywheel. It is all done by the scribed line on the pump flange and the adjustable pointer on the triangular mounting block. However if this is the engine that I got a question about directly and which the boat's vendor had a lot to say about in another thread I fear you will need to do a lot more than just set the pump timing. I warned you about the "quality" of the aledged overhaul and the other thread indicated that my warning may well have been well founded. From the information in the other thread I would question the competence of those who "overhauled" it.

 

I have seen nothing to reduce my fears about that overhaul and in fact I am even more worried now. There are two further aspects of pump timing on the 1.5 that you need to consider and both require you to know about TDC and the injection point. First of all you have to be sure the camshaft timing is correct because the camshaft drives the injector pump and then you need to be sure the pump's skew gear drive is in good condition and correctly timed. IF either of those are wrong the timing marks on the flange and mounting block are useless. Then there is the question of how, if at all, the ponter on the mounting block was set. This should involve the use of a special tool to take all the backlash out of the camshaft drive and gears.

 

If you can set the engine to no. 1 @ 22 degrees BTDC compression and pull the injector pump the master spline on the drive should be at the 5 o'clock position.

 

There is supposd to be a 1 & 4 TDC mark on the flywheel. That needs to be at the "top" to quote an online manual. Then you mark the engien backplte to give a dataum. Count the number of flywheel teeth and devide 360 by that number. Then calculate how many teeth make up 22 degrees. Rotate the flwheel so the relvant tooth or space alignes with your datum.

 

When the engine is at TDC there is a dimple in each timing gear. These should line up with themselves and the centre of the crank & camshaft.

 

When you say you saw the fuel running down the injector pipes do you mean the outside or the inside. If you mean the inside then they are not injector pipes and secondly you have a potential BSS failure on your hands.

[p6rob]

Simply timing the 1.5 injector pump does not require any timing marks on the front pulley or flywheel. It is all done by the scribed line on the pump flange and the adjustable pointer on the triangular mounting block. However if this is the engine that I got a question about directly and which the boat's vendor had a lot to say about in another thread I fear you will need to do a lot more than just set the pump timing. I warned you about the "quality" of the aleged overhaul and the other thread indicated that my warning may well have been well founded. From the information in the other thread I would question the competence of those who "overhauled" it.

 

Indeed. There are some big bills for engine parts and labour but that is proving not necessarily a sign of good value. I'm not sure if it would be useful to see the vendors thread about the engine saga or not. Might put me off...

 

 

I have seen nothing to reduce my fears about that overhaul and in fact I am even more worried now. There are two further aspects of pump timing on the 1.5 that you need to consider and both require you to know about TDC and the injection point. First of all you have to be sure the camshaft timing is correct because the camshaft drives the injector pump and then you need to be sure the pump's skew gear drive is in good condition and correctly timed. IF either of those are wrong the timing marks on the flange and mounting block are useless. Then there is the question of how, if at all, the ponter on the mounting block was set. This should involve the use of a special tool to take all the backlash out of the camshaft drive and gears.

 

If you can set the engine to no. 1 @ 22 degrees BTDC compression and pull the injector pump the master spline on the drive should be at the 5 o'clock position.

 

This is what I've been hoping to do. Like you rightly say the competence of the people who have worked on the engine needs questioning at each stage, if only for peace of mind.

 

 

There is supposed to be a 1 & 4 TDC mark on the flywheel. That needs to be at the "top" to quote an online manual. Then you mark the engine backplate to give a datum. Count the number of flywheel teeth and divide 360 by that number. Then calculate how many teeth make up 22 degrees. Rotate the flywheel so the relevant tooth or space aligns with your datum.

 

That is useful to know thank you.

 

When the engine is at TDC there is a dimple in each timing gear. These should line up with themselves and the centre of the crank & camshaft.

 

I'm reasonably confident this has been set correctly, although it is still a nagging doubt.

 

When you say you saw the fuel running down the injector pipes do you mean the outside or the inside. If you mean the inside then they are not injector pipes and secondly you have a potential BSS failure on your hands.

 

I mean with the injector pipes loosened to bleed the fuel system, diesel runs down the outside of the pipe, With the injector pipes tightened up, there is no diesel leakage.

[p6rob]

Hi, Still struggling with the engine. It's been overheating and smokes a lot. I've flushed out loads of rust but it still overheated so, I removed the drain tap from the block and discovered that part of the water jacket was still blocked, so, thinking the water channels were blocked solid I removed the head. While the channels aren't blocked, there are quite a few large rust flakes that show there is still more reverse flushing to do.

I also discovered a number of issues with the cylinder head while it was off.

1. Number 2 pre combustion chamber falls out, though I gather this is more an inconvenience than an issue.

2. Through the water jacket opening by number four on the head, there is what looks like a rusty rod. Without pulling it all the way out, it looks plausible that it could be there to hold the pre combustion chambers in place (though I suspect it's not). I couldn't see it mentioned in the workshop manual which makes me suspicious. It feels long enough that it could be broken around number two which could explain why it's chamber is loose.

3. There are three water jacket plugs on the mating face of the cylinder head. The centre one of these has pushed through and is not sealing. I'm not sure how concerned to be about this as the gasket should seal the hole, but as there is a cooling issue, fixing it and ruling it out makes sense.

 

Timing:

Is there anyone near Sherborne Wharf who has the timing tool to loan or hire please, or could come and set the pointer position correctly.

Also, is there anywhere that sells the bush for the pump drive gear. As it's apart think it ought to get changed.

[Tony Brooks]

I think that you will find that "rod" is a part of the supporting wire for the mould core from when the block/ head was cast. They remove the core sand via the core plugs etc but BMC often seemed to leave at least one of the wires in the block or head.

 

I do not like the sound of pre-combustion chambers simply falling out and I have never known it. I wonder if there is a crack in the head that has allowed the hole to expand. That could also explain the overheating.

 

Water jacket plugs? I know there can be small brass plugs.

 

Did you ever pressure test the system before stripping the engine because with overheating that would be one of my tests to ensure no cylinders or the head have cracked. Did you test the coolant using fluid that changes colour if exhaust gas is in the coolant?

[Geoff Taylor]

I think that you will find that "rod" is a part of the supporting wire for the mould core from when the block/ head was cast. They remove the core sand via the core plugs etc but BMC often seemed to leave at least one of the wires in the block or head.

 

I do not like the sound of pre-combustion chambers simply falling out and I have never known it. I wonder if there is a crack in the head that has allowed the hole to expand. That could also explain the overheating.

 

Water jacket plugs? I know there can be small brass plugs.

 

Did you ever pressure test the system before stripping the engine because with overheating that would be one of my tests to ensure no cylinders or the head have cracked. Did you test the coolant using fluid that changes colour if exhaust gas is in the coolant?

 

Hi, I too thought it odd to have a loose combustion chamber as they are usually fitted by the shrink fit method on most engines, on referring to the workshop manual I have,section B3 page 41 states that upon removing head, chambers may fall out and to make sure that they are replaced in the same order as they are machined together with the head. Personally I would not like a loose fit as it could create hotspots. If my memory serves me right, the 2.2 diesel Land Rover series II shop manual mentioned this. The only instance of dropping chambers I have come across was when the cylinder heads had experienced severe overheating and this was not on BMC 1.5s.

[p6rob]

I took it from the manual that it was not unusual for the pre combustion chambers to be loose. However the loose chamber is very loose, whereas all the others are a good tight fit and the joins are barely visible.

I haven't checked the coolant for combustion gasses, but did do a compression test. All cylinders were between 410 and 420 psi, which I think is well within spec for a healthy engine.

 

This engine had a crank grind, hone and new rings, recon cylinder head, recon injectors and injector pump in February last year but didn't run until March this year.

 

Yes, three small brass plugs which should be press fitted into the head surface. One is loose and actually now floating in the water jacket of the cylinder head.

It sounds like getting the head cheaked by a machine shop would be a good idea.

[p6rob]

The head has been dispatched to a machine shop which was recommended to me by someone at Valley Cruisers. If it works out to be scrap, does anyone have a spare BMC 1.5 head for sale please?

 

Robert

[p6rob]

Hi,

Some good news... ...I think. The cylinder head has come back from the machine shop. It's fitted, valves adjusted and almost everything has been re-installed. Found a few suspect water pipes and connectors which replacements have arrived for today, so hopefully the engine will be running before Tuesday when I've got someone coming to weld the skin tank.

 

I just hope all this expense and effort cures the running problems so I can get out onto the cut for the next few months.