Perkins 4.326 (M90) Heat Exchanger decisions

[sfellows]

After previous recent posts, we've determined that our failed lowline M90 Heat Exchanger is no longer available and our options appear to be limited for a replacement. Has anyone replaced their Heat Exchanger for the combined Perkins M90 Bowman Exhaust/Header/Heat Exchanger Kit? If so what was your experience?

It's also been suggested that we Sikaflex the end-cap (which is warped and leaking as well as the aluminium housing facing being corroded) but the engineer won't do this as he said the Sikaflex will then block the heat exchanger. Any thoughts?

 

[rogerthebodger]

Is this the heat exchanger

f so it the sam type I got aluminum welded and Sikaflex the o rings in place without blocking the tube stack

https://flic.kr/p/WVjpXj

Different engine but same type of heat Exchange

If your "Engineer" is not prepared to fix it get a different "Engineer"

 

[sfellows]

No, unfortunately its not the same Heat Exchanger. But I may have a go at putting Sikaflex on the end cap as a temporary measure. I don't think it will make things worse..... Thanks for your help.

 

[rogerthebodger]

Can you post a picture of the heat exchanger you have as I do also have a Perkins 4 236 engine with a different heat exchanger

 

[sfellows]

Here's a picture with the Heat Exchanger circled....

 

[Boater Sam]

I think a good workshop would be able to renovate or fabricate a new one. Seen some brilliant welding jobs done on so called irreparably things.

 

[rogerthebodger]

I think a good workshop would be able to renovate or fabricate a new one. Seen some brilliant welding jobs done on so called irreparably things.

I agree with that

I have a local welder near me that does a great job of welding all types of material

Repairs of damaged aluminum wheel local to the OP may be able to help

 

[Tremyporth]

Here's a picture with the Heat Exchanger circled....

I have a similar engine. A few years ago I flushed and cleaned out the entire cooling system, including stripping, cleaning and re-sealing all three heat exchangers. Gearbox oil, sump oil, and coolant. The end caps are solid chunky bronze castings. I doubt very much if they have warped. Dismantling the heat exchangers often is not easy, because the mix of aluminium bodies, mild steel bolts, bronze caps and tubes plus salt water equals corrosion and seized bolts to contend with. If the exchanger is off the engine and you are able to get it apart, then as others have suggested, see if you can get the aluminium body repaired. If not, then consider whether your existing header tank and water-cooled manifold are in good order. If they are, it may be best to leave them in place. If they aint broke, why replace them? Some of the nuts and bolts holding them in place can be utter pigs to undo if those parts of the engine have not been worked on since it was installed. In fact, they may shear off, and need cutting or drilling out. Not easy with restricted access, and expensive if you have to pay somebody else to do it. So then, you could look either for a like for like replacement second hand heat exchanger from a dealer in secondhand marine engines. One in Dorset has been mentioned on the Forum previously. Or a new heat exchanger of suitable size, which could be mounted remotely and connected to the existing plumbing with new flexible pipework or hoses. Maybe slightly complicated plumbing: I seem to recall the thermostat by-pass has to be allowed for. A remotely mounted heat exchanger would have the additional benefit of allowing much improved access to the fuel lift pump and various coolant drain taps on the engine block.

 

[sfellows]

Thanks for all your replies. We have already been in contact with the second hand dealer in Dorset but looks like no like for like replacement. We are going to attempt a repair next week with Hylomar and a new gasket and then Sikaflex if this doesn't work before deciding next steps. The end-cap is definitely warped by a mm! We have no idea how. Perhaps getting the end-cap skimmed might help if we can't seal the end? Our engineer has suggested a separate Heat Exchanger and recognises the complicated plumbing (although not sure about the thermostat bypass). Going to talk to Bowman in Birmingham on Monday as they are on holiday this week! Oh joy.

 

[sfellows]

Update: Bowman no longer support the Perkins 4.326, but they pointed me to Lancing Marine who were super helpful. There are two replacement options, one of which is a kit for a like for like replacement, so if our plan to repair with a new seal and, potentially, Sikaflex does not work I think we'll be getting the kit. For those in a similar situation, the kit is an EC 140. For those that want a full header/exhaust/heat exchanger (basically a 4.326 marinisation kit) it's a PE 390.

 

[RunAgroundHard]

Excellent, thanks for the update, I too have the same engine.