Engine running hot / Blow-by smoke / cooling issue

[SwiftRanger]

hello!

We have a Universal 5444 that's acting strange. A while back we the engine overheated and after inspection, noticed that we were low on coolant. Topped off the coolant and "fixed" the problem. Engine ran great for about 100 hours.

Now we are experiencing the a similar problem just a little less severe (the engine is running consistently 15-20 degrees over normal operating temp. Also our crankcase vent is throwing out a significant amount of smoke that i've never noticed before. We've always had some blow-by but never smoke.

Here's all the things i'm done to no avail:

-flushed the cooling system, re-bled system... no change

- Thinking this was possibly a head gasket leak, I did an oil analysis and it came back normal.

- Checked water pump">raw water pump and impeller - all good (new pump and impeller 6 months ago)

- Checked heat exchanger, appears to be free from obstructions (also i flushed this last year)

- Replaced thermostat, no change

- Insepcted water pump, all good


Any advice on where i should look next? The engine is 40+ years old... i'm a little scared an issue with a piston. Fingers crossed!

thanks for your time,
Patrick

[Tsuru]

Even with the positive oil analysis I'd consider a head gasket leak test kit.
https://www.google.com/search?client...UTF-8&oe=UTF-8

[kapnd]

A 40 year old motor is likely to have some aches and pains that come with being old!
Westerbeke.com stocks some parts, but this motor has been out of production for a good many years.
I just helped a friend locate a new head for his, was just over $1000.
Found a screen on the fuel pump intake to be clogged, repairing that made a big difference!
The block uses cylinder liners, so is rebuildable.
Have you closely examined the coolant circulation pump?
How about a leak down test, or even a simple compression test?

[skipperpete]

I’m sorry Patrick but I can’t offer you any encouraging advice regarding your Universal engine, the excessive crankcase pressure and smoke doesn’t sound good. It could be due to a head gasket blown across to the pushrod gallery and that would be a good thing, a new gasket and a valve grind plus a timely inspection of the bores and you’re back in business but there is the more likely situation where the pistons had some minor level upper cylinder seizure or scuffing from the initial overheat….not enough to lock up the engine but enough to bugger up the cylinder walls, rings and pistons hence the smoky blow by.
Take Kapnd’s advice and do those cylinder tests, then you’ll know how to proceed. Hopefully its just a head gasket.

[SwiftRanger]

thanks to everyone for the quick replies!

I'll go ahead and do a proper head gasket leak test.


One other thought I had was regarding the injectors. We were in Mexico for a few months and picked up some mediocre fuel (we've had to drain our water seperator more times than i'd like). Small chance it could have damaged an injector.


Do you think a bad injector could case this much havoc?

[CMH]

Recommend checking for constricted thru-hull
Chris

[skipperpete]

Originally Posted by SwiftRanger

thanks to everyone for the quick replies!

I'll go ahead and do a proper head gasket leak test.


One other thought I had was regarding the injectors. We were in Mexico for a few months and picked up some mediocre fuel (we've had to drain our water seperator more times than i'd like). Small chance it could have damaged an injector.


Do you think a bad injector could case this much havoc?

Anything’s possible but usually an indirect injection engine (pre combustion type) handles contaminated fuel better than direct injection engines. First of all, the injectors are of a type that has a fairly large hole in the nozzle thats practically impossible to block. Unlike direct injection engines, initial combustion takes place in the precom chamber so there’s no chance for a faulty injector spray pattern to impinge on the piston crown or cylinder walls ( which leads to piston erosion and ring damage) and cause the heavy breathing that you described earlier.
Water in diesel fuel is capable of blowing the spray tips off multi hole atomisers because it expands dramatically when it changes to steam as it meets the heat of compression when the needle pops at the moment of injection, but again, only direct injection engine nozzles with tiny multiple spray holes.