KAD300 Exhaust gasket replacement

[frazion]

Looking for some thoughts. I've pulled off a pile of ancillaries to get to the heat exchanger to do an off-engine flush and clean (browny rusty coating in the coolant side) and given that im at the exhaust, im wondering if its worth while changing the gaskets there since im there. There's nothing wrong that im aware of although there is a bit of rust i could get cleaned out while its off.

It's just another job, and im sure i could keep going but dont really want to open up another can of worms, as it is, ive still got the oil cooler to do and id rather just get the core out without removing the whole oil housing from the body.

Some of these things are good to do for preventative maintenance but some aren't.

 

[alt]

I replaced the exhaust manifold gaskets on one of my KAD300's last winter as there was a slight coolant weep from 2 of them. It wasn't a hard job, just took a while. BUT, I have exceptional engine access!

A friend of mine recently had to loosen the exhaust manifold nuts on his KAD32 and after tightening up again, they were leaking coolant. So, I suspect, if you need to loosen the exhaust manifold nuts (ie. to remove other items), you're going to break the 'seal', so i'd change them while i'm at it.

 

[frazion]

I replaced the exhaust manifold gaskets on one of my KAD300's last winter as there was a slight coolant weep from 2 of them. It wasn't a hard job, just took a while. BUT, I have exceptional engine access!

A friend of mine recently had to loosen the exhaust manifold nuts on his KAD32 and after tightening up again, they were leaking coolant. So, I suspect, if you need to loosen the exhaust manifold nuts (ie. to remove other items), you're going to break the 'seal', so i'd change them while i'm at it.

Thanks, good to know. The engines are coming out anyway so access wont be an issue. Just wanted to avoid another job as its easy to spiral! However, it looks like its going to get done :-/

 

[Mr Googler]

If you get to that stage…you know you’ve over done it ??

 

[frazion]

Hah! Hoping not, both engines are going to be beside the boat so don’t want them out for more than a few days! Thankfully, access is pretty good in the engine bay but I do want to get any spray paint and derust if done while they are out.

 

[alt]

I'd be changing the gaskets if the engine is out, regardless. You don't want to put them back in to find the gaskets leaking.

PS. When I installed the new gaskets and tightened to spec, they leaked! Panic stations. I warmed the engine, let it cool and gave each nut another 1/2 turn to tighten.... problem solved!

 

[frazion]

I'd be changing the gaskets if the engine is out, regardless. You don't want to put them back in to find the gaskets leaking.

PS. When I installed the new gaskets and tightened to spec, they leaked! Panic stations. I warmed the engine, let it cool and gave each nut another 1/2 turn to tighten.... problem solved!

I meant to ask, did you use exhaust paste/sealant with the gaskets?

 

[frazion]

For what its worth for anyone stumbling on this thread, once the exhaust came off, there was a whole load of rust on the mating faces and underneath, so well worth the effort. it also led to identifying failed seals that i wouldnt have known about including the thermostat housing to pump. so it just goes to show, its worth doing what you can when the engines are out....but im not touching the head gasket!

 

[dr_oli]

I'd be changing the gaskets if the engine is out, regardless. You don't want to put them back in to find the gaskets leaking.

PS. When I installed the new gaskets and tightened to spec, they leaked! Panic stations. I warmed the engine, let it cool and gave each nut another 1/2 turn to tighten.... problem solved!

Can you recall tightening specs?

 

[alt]

Can you recall tightening specs?

Can't remember, but i'm almost sure someone here mentioned the specs before!