Perkins MC42 - 104.19 Marinised by Duffields - Thermostat Issue

[Webafloat]

Hi All, Who has this engine and in particular this thermostat setup?

 

My issues was the engine not heating the water, has been fine the last 8 months. Issue cam about when the Bowman end cap on the heat exchanged split, sending coolent everywhere. Replaced and refilled with coolent and bled system and still not hot water. Moved on to checking the thermostat, taking the cover off i was met with a weird hard plastic or possible rubber that has aged in hot water, it came out but very misshaped. Tested thermosat with good old pan of water, opened as it should in hot water. Bought a new one for a perkins 104-19 engine, plus sourced a spring that after researching the engine was listed. On fitting said spring to me it was not strong enough and that the water pressure could just move the whole thermosat in situ...anyway fitted with new thermo, spring etc and still not hot water.

 

Im thinking that perhaps the hard tube is the way to go, buy a piece that attaches to back of plate and outside of thermosat, then drill 3 holes like the old one.

 

I do not know engine temp and gauage broken and dont have testing equipment. I know if i run engine for two hours and take rad cap off the water is luke warm. So i preseum water is just going round the engine and calorifier in one big loop and never getting hot. If i run the Alde boiler the water does heat up so I know the calorifier tnk is OK.

 

Would welcome thoughts and help, many thanks.

 

[Jen-in-Wellies]

When you say the engine is not heating the water, do you mean you aren't getting hot water from the calorifier?

If so, then:

I don't know this engine, or marinisation, but generally, the coolant loop to a calorifier comes off the engine upstream of the thermostat. The thermostat has no effect on it. If however, you've drained off coolant and opened up the thermostat housing, then there is a good chance there is now an air lock in the pipework to the calorifier. If this is the case, you need to bleed any air from high points in the hoses and pipes to and from the cauliflower to get coolant to circulate round this loop.

Jen

[Webafloat]

18 minutes ago, Jen-in-Wellies said:

When you say the engine is not heating the water, do you mean you aren't getting hot water from the calorifier?

If so, then:

I don't know this engine, or marinisation, but generally, the coolant loop to a calorifier comes off the engine upstream of the thermostat. The thermostat has no effect on it. If however, you've drained off coolant and opened up the thermostat housing, then there is a good chance there is now an air lock in the pipework to the calorifier. If this is the case, you need to bleed any air from high points in the hoses and pipes to and from the cauliflower to get coolant to circulate round this loop.

Jen

Have tried to bleed, no air on valve on Calorifier or the return valve on engine, have the bled the skin tank. Surely If air was stopping going to calorfier surely the engine would still get hot! I can run the engine for two hours and take the rad cap off heat exchanger and the water is luke warm and engine still just warm to touch!

 

regards pete

[Tony Brooks]

2 minutes ago, Jen-in-Wellies said:

When you say the engine is not heating the water, do you mean you aren't getting hot water from the calorifier?

If so, then:

I don't know this engine, or marinisation, but generally, the coolant loop to a calorifier comes off the engine upstream of the thermostat. The thermostat has no effect on it. If however, you've drained off coolant and opened up the thermostat housing, then there is a good chance there is now an air lock in the pipework to the calorifier. If this is the case, you need to bleed any air from high points in the hoses and pipes to and from the cauliflower to get coolant to circulate round this loop.

Jen

 

having been discussing this with the OP it seems that the hot water take off for the calorifier is on the rubber moulding at the back end of the manifold cum header tank. On a heat exchanger boat this would be the exit of raw water gong to a wet exhaust. There is no sign of any securing clips for a heat exchanger core so it is fair to assume there is not one in the manifold.

 

This means the calorifier take of is on the skin tank side of the thermostat so in my view circulation through the calorifier coil is in no way certain. I have suggested locating the can heater take off point and using that or if there is not one trying a 12V "solar"/car pump to ensure circulation through the coil.

 

It seems Duffields have plonked their marine manifold over the thermostat position where the normal  thermostat housing would be located with means there is nothing to hold the thermostat in place. I think that is what that distorted rubber hose was for but the OP says Duffields fitted a spring, but the spring he has obtained does not seem string enough and he thinks the circulating pump pressure is lifting the stat of its seating. I have suggested that there is no reason to not fit a stronger spring of suitable dimensions if he can find one or to make up another length of hose. The state of that chunk of hose and also the rubber sealing ring that had fallen off the thermostat makes me suspicious that the coolant had been contaminated by hydrocarbons at some time. I also wonder if a carefully cut length of plastic drain pipe would do the job but if a pipe or hose is used it will need holes in the side to allow coolant to flow into the manifold. Personally I have  some doubts about the circulating pump pushing the thermostat off its seat.

 

The OP has not told you that he has no reliable temperature gauge so does not really know how hot the engine is running so there is no way of knowing if it s lack of heat in the coolant or lack of circulation through the coil.

 

Hope this clarifies things a bit. The thermostat thing seems like a right bodge to me.

Just now, Webafloat said:

Have tried to bleed, no air on valve on Calorifier or the return valve on engine, have the bled the skin tank. Surely If air was stopping going to calorfier surely the engine would still get hot! I can run the engine for two hours and take the rad cap off heat exchanger and the water is luke warm and engine still just warm to touch!

 

regards pete

 

That confirms it is a thermostat problem, so look for  a different spring and make sure the stat you bought is one with the sealing ring around its  flange. If you can't find one then cut another length fo hose but make sure you cut holes in the side to et the coolant out of the hose.

[Webafloat]

5 minutes ago, Tony Brooks said:

 

having been discussing this with the OP it seems that the hot water take off for the calorifier is on the rubber moulding at the back end of the manifold cum header tank. On a heat exchanger boat this would be the exit of raw water gong to a wet exhaust. There is no sign of any securing clips for a heat exchanger core so it is fair to assume there is not one in the manifold.

 

This means the calorifier take of is on the skin tank side of the thermostat so in my view circulation through the calorifier coil is in no way certain. I have suggested locating the can heater take off point and using that or if there is not one trying a 12V "solar"/car pump to ensure circulation through the coil.

 

It seems Duffields have plonked their marine manifold over the thermostat position where the normal  thermostat housing would be located with means there is nothing to hold the thermostat in place. I think that is what that distorted rubber hose was for but the OP says Duffields fitted a spring, but the spring he has obtained does not seem string enough and he thinks the circulating pump pressure is lifting the stat of its seating. I have suggested that there is no reason to not fit a stronger spring of suitable dimensions if he can find one or to make up another length of hose. The state of that chunk of hose and also the rubber sealing ring that had fallen off the thermostat makes me suspicious that the coolant had been contaminated by hydrocarbons at some time. I also wonder if a carefully cut length of plastic drain pipe would do the job but if a pipe or hose is used it will need holes in the side to allow coolant to flow into the manifold. Personally I have  some doubts about the circulating pump pushing the thermostat off its seat.

 

The OP has not told you that he has no reliable temperature gauge so does not really know how hot the engine is running so there is no way of knowing if it s lack of heat in the coolant or lack of circulation through the coil.

 

Hope this clarifies things a bit. The thermostat thing seems like a right bodge to me.

Hi Tony, think the plastic pipe is going to be the answer I agree, I dont want to start relocating pipes as the engine has been like this since 1983 without issue as far as i know, only owned the boat 8 months or so but has been working fine up till now. I have found a couple of local boat engineers hopefully one of them will come and take a look. You have been very helpfull on our email conversation, sadly I dont know how to relocate pipes, fit heaters etc.

[Tony Brooks]

Been looking for some suitable (guessed size)  stainless steel springs without much luck but suddenly though about a used valve spring off a fairly modern engine. Modern valve springs seem to be far weaker that those on BMCs etc. so may be ideal as long as the ID is larger than the raised part of the thermostat flange. I am sure it would rust eventually but should give many years of service. You could cut to length with a grinder.

[Webafloat]

57 minutes ago, Tony Brooks said:

Been looking for some suitable (guessed size)  stainless steel springs without much luck but suddenly though about a used valve spring off a fairly modern engine. Modern valve springs seem to be far weaker that those on BMCs etc. so may be ideal as long as the ID is larger than the raised part of the thermostat flange. I am sure it would rust eventually but should give many years of service. You could cut to length with a grinder.

could be a shout, think i will remove the thermosat and spring and go to a motorists part place, we have an old school one near us with boxes everywhere, health hazzard for sure but they will have a pipe or a spring that longer and stronger.

[Tony Brooks]

Another thought. I suspect that if you look into the manifold chamber you may see some bolt heads that secure the manifold to the original automotive thermostat housing. If there are and they are suitably placed a couple of bent pieces of strip metal that could be used to clamp the thermostat flange in place. They would act like a larger versions of the clips that hold stove door glass in place.

[Richard Carter]

3 hours ago, Webafloat said:

Hi Tony, think the plastic pipe is going to be the answer I agree, I dont want to start relocating pipes as the engine has been like this since 1983 without issue as far as i know, only owned the boat 8 months or so but has been working fine up till now. I have found a couple of local boat engineers hopefully one of them will come and take a look. You have been very helpfull on our email conversation, sadly I dont know how to relocate pipes, fit heaters etc.

1983 is too early for an MC42, in 1990 (or 1991?) we had the first one fitted to a canal boat in the hire fleet at UCC in Braunston (up to then it had been the 4.108) - it may be worth trying Jona at UCC to see what he can remember of the MC42 cooling, as we ran several in the fleet in the 90s.

[Webafloat]

20 minutes ago, Richard Carter said:

1983 is too early for an MC42, in 1990 (or 1991?) we had the first one fitted to a canal boat in the hire fleet at UCC in Braunston (up to then it had been the 4.108) - it may be worth trying Jona at UCC to see what he can remember of the MC42 cooling, as we ran several in the fleet in the 90s.

Hi Richard Jona @ UCC sorry whos or where can i contact on this please?

[Richard Carter]

15 minutes ago, Webafloat said:

Hi Richard Jona @ UCC sorry whos or where can i contact on this please?

Union Canal Carriers is the hireboat company in Braunston, Jona(than) Hewitt is the engineer - I left 20 years ago so probably better check office phone no. on their homepage (even if landline numbers tend not to change ... ).

[Webafloat]

UPDATE:

 

Replaced Thermostat

Found the correct spring to hold thermostat in place feels solidly in place.*

Bled whole system, skin tank, Forced air both ways , from rad cap pump and forced air back from Outlet pipe from calorifier, coolent runs freely.

When i start engine from cold, no coolent comes from calorifier outlet return to engine until thermostat opens then coolent runs from calorifier return.

 

Im trying to get a new water temperature sender as my gauge is not working (when i can source one appears only abroad with my VOD one) but no hot spots, coolent level is always the same, no leaks... we used to but now Bowman rubber replaced thats fixed that leak.

 

BUT engine always gave us hot water from just running engine either whilst crusing or just moored up. It now is just luke warm, I CAN PUT MY FINGERS IN THE HEAT EXCHANGER TANK EVEN AFTER ENGINE RUNNING FOR 2 HOURS.

 

*Now the black plastic thing i think acted with two roles to play, 1. held thermostat in place  2. looks like it acted as a sort of restrictor  to stop water flowing completly.

 

Calorifier has two coils, one for engine loop and one for the ALDE Boiler, ALDE coil does heat up, Ive spent weeks trying to solve and 4 bottles of gas to heat my water is getting expensive.

 

Can anyone offer any suggestions or even a better  suggest a  marine heating engineer specialist who wants to come ond fix??? Currently in Oxford @Tony Brooks can i tempt you out of retirement for a problem solving trip to Oxford.

 

Cheers Guys

 

[Tony Brooks]

1. If the thermostat is t open very little coolant will flow into the header tank, so virtually none will go through the calorifier. That is as I would expect on your system.

 

2. I have no idea why the header tank is not getting up to the thermostat temperature unless the skin tank is somehow fed from the engine side of the stat.

 

3. A closed thermostat will virtually stop all coolant circulation so is  a very good restriction. The only time that is not true if the water pump produces enough pressure to force a bellows type stat open OR if it manages to lift the thermostat off it's seat. At present I think the spring may not be strong enough.

 

 

[Webafloat]

1 minute ago, Tony Brooks said:

1. If the thermostat is t open very little coolant will flow into the header tank, so virtually none will go through the calorifier. That is as I would expect on your system.

 

2. I have no idea why the header tank is not getting up to the thermostat temperature unless the skin tank is somehow fed from the engine side of the stat.

 

3. A closed thermostat will virtually stop all coolant circulation so is  a very good restriction. The only time that is not true if the water pump produces enough pressure to force a bellows type stat open OR if it manages to lift the thermostat off it's seat. At present I think the spring may not be strong enough.

 

 

1. so we agree works as it should

2. Could there be a second thermostat gizmo thats stuck open?

3. Ive stretched the spring a little and feels much stronger, starting to think of putting the blacl plastic pipe thing back in.

 

Can you recommend any companies or marine engineer who i could pay to come and fix?

[Tony Brooks]

2 minutes ago, Webafloat said:

1. so we agree works as it should

2. Could there be a second thermostat gizmo thats stuck open?

3. Ive stretched the spring a little and feels much stronger, starting to think of putting the blacl plastic pipe thing back in.

 

Can you recommend any companies or marine engineer who i could pay to come and fix?

 

1. it clearly does not work a sit should, the engine is not getting up to temperature.

 

2. No idea, it seems that you almost have a one off engine, but the way the calorifier is fed I very much doubt there is another thermostat.

 

3. I told you some time ago that you may need to fabricate something from rigid plastic pipe. The black thing you sent images of looked very misshapen but I think a strong spring of the correct length would be better because it would require far less precision in cutting to length and would allow you to assess its length by seeing when you have to start pulling the square cover down with the bolts.

 

Perhaps other could recommend a very experience Perkins engineer. I would never drop an engineer in it by recommending they for this particular job.

[Webafloat]

1 minute ago, Tony Brooks said:

 

1. it clearly does not work a sit should, the engine is not getting up to temperature.

 

2. No idea, it seems that you almost have a one off engine, but the way the calorifier is fed I very much doubt there is another thermostat.

 

3. I told you some time ago that you may need to fabricate something from rigid plastic pipe. The black thing you sent images of looked very misshapen but I think a strong spring of the correct length would be better because it would require far less precision in cutting to length and would allow you to assess its length by seeing when you have to start pulling the square cover down with the bolts.

 

Perhaps other could recommend a very experience Perkins engineer. I would never drop an engineer in it by recommending they for this particular job.

Ive tried various car parts places about a spring...computer says NO response each time. Any suggestions where or the typeof company i need to locate, so i could get the right grade plastic pipe that could be submerged in coolant?

 

Can a calorifier go wrong? Surely is just a tank of water with two coils, ALDE one works, engine does not but coolant flowing so calorifier is fine water temp is not!

[Tracy D'arth]

6 minutes ago, Webafloat said:

Ive tried various car parts places about a spring...computer says NO response each time. Any suggestions where or the typeof company i need to locate, so i could get the right grade plastic pipe that could be submerged in coolant?

 

Can a calorifier go wrong? Surely is just a tank of water with two coils, ALDE one works, engine does not but coolant flowing so calorifier is fine water temp is not!

Air locks in the coil and pipes to and from are the usual reasons for no circulation.

 

Have you tried restricting the hose to the skin tank by crushing it a bit to reduce the flow?

[Tony Brooks]

Just now, Webafloat said:

Ive tried various car parts places about a spring...computer says NO response each time. Any suggestions where or the typeof company i need to locate, so i could get the right grade plastic pipe that could be submerged in coolant?

 

Can a calorifier go wrong? Surely is just a tank of water with two coils, ALDE one works, engine does not but coolant flowing so calorifier is fine water temp is not!

 

I am on the verge of giving up on this because I am fed up with repeating myself. If you can hold your fingers in the header tank two hours after you start running then the engine is not getting hot enough so it won't heat the calorifier much - as I have explained to you before. That is what you need to rectify first.

 

Look, you were told the plastic thing was a bodge Duffields did to get the engine to a show. That means it is a Duffields produced MARINE part. No wonder car parts places can't help. To repeat what I have already told you. If this were mine I would be looking for a valve spring that neatly fits the thermostat flange and is long enough so it holds the square plate about 6mm clear of the manifold until you tighten it down. You can cut springs to length with a grinder but fi you do put the cut end against the square plate.

[Webafloat]

Sorry Tony, Thank you for all your help I really do appreciate your time trying to help me. I struggle to fully understand as im dyslexic, so reading and understand can be tricky. I'm not an engineer or a mechanic so not sure where to go to find these parts.

Yes i understand water not getting hot enough and need to address this.

 

I did ask a car auto parts about a valve spring, they just laughed at me as a valve spring would not move to tighten up as they so hard to compress and need a special valve compression tool and not put in place and push cover on to bolt up. Or am i referring to a different valve spring. Im happy to try anything, just need to know where i can get a spring or the type of company that sells them.

This is the spring i currently have.

 

regards pete

[Tony Brooks]

That spring looks far too weak to me and it seems an automotive part, not a marine one. Have you fitted it the right way round? The big end looks as if it might be a larger diameter than the thermostat flange.

 

I would take the plastic bit to a good hardware shop or an engineering suppliers to see if they can match a nice stiff spring for diameter and ideally length. Young Engineer Supplier is listed as being in Oxford but have no website.

 

 You can compress Beta and Vetus valve springs by just pushing down on them these days but in any case as long a spring is not too long the bolts/nuts & studs holding the square cover on will act as a spring compressor.

 

 

 

 

[Webafloat]

2 minutes ago, Tony Brooks said:

That spring looks far too weak to me and it seems an automotive part, not a marine one. Have you fitted it the right way round? The big end looks as if it might be a larger diameter than the thermostat flange.

 

 

 

 

 

Hi thanks, spring was from perkins engine part suppliers, same diameter both ends, will try the enginners tomorrow, will google some options.

 

[Tony Brooks]

10 minutes ago, Webafloat said:

Hi thanks, spring was from perkins engine part suppliers, same diameter both ends, will try the enginners tomorrow, will google some options.

 

 

I don't think that you understand. You were told Duffields made that plastic thing to get the engine to a show so it is not a Perkins part. The base Perkins engine does not have the marine manifold. By all means put the plastic thing back but make sure it sits squarely on both the thermostat and the square cover but holds the square cover a little proud of the manifold until you pull it down with the nuts/bolts. If the cover is not held proud or if the plastic bit is distorted so it only pushes on one side of the thermostat flange  it is unlikely to hold the thermostat in place as it should.

 

I have some thickish wall  silicon hose form Hills Rubber of Reading that might do the job if they stock any of the correct i.d. However I fear that by the time you have cut you holes in the side it may not have enough strength and may buckle.

Edited February 28, 2022 by Tony Brooks

[Webafloat]

Hi

 

https://www.amazon.co.uk/Socket-Fusion-Straight-Fitting-Coupling/dp/B01F0TJK0Q

 

This type dimensions work i need internal 36/38mm , will try and source this and cut to length.

[Tony Brooks]

9 hours ago, Webafloat said:

Hi

 

https://www.amazon.co.uk/Socket-Fusion-Straight-Fitting-Coupling/dp/B01F0TJK0Q

 

This type dimensions work i need internal 36/38mm , will try and source this and cut to length.

 

And then cut the holes in the side so the water exiting the thermostat can get out of the tube.  I think any  decent plumbers merchant will stock them but you may need some pipe as well so you can get the length correct. As a guess I think I would want the new piece to hold the square cover about 10 thousandths of an inch  clear of the manifold face before tightening down.

[Webafloat]

Just now, Tony Brooks said:

 

And then cut the holes in the side so the water exiting the thermostat can get out of the tube.  I think any  decent plumbers merchant will stock them but you may need some pipe as well so you can get the length correct. As a guess I think I would want the new piece to hold the square cover about 10 thousandths of an inch  clear of the manifold face before tightening down.

Yes agree, all makes sense i just need to find a pipe or spring to keep thermostat seated. Will trawl engineer supplies, plumbing supplies etc to find such a bodge!

 

Thanks Tony