4.3L Exhaust Manifolds & Thermostat

[riverratjody]

I have a '98 4.3L Mecruiser 262 with the batwing manifolds. I purchased my boat this past season and am trying to get it ready for Spring. I think I have the correct parts to convert to the 2 piece (elbow tube and upper & lower bellows), and now need to purchase the manifolds & elbow risers. I can go with the Mercruiser OEM equipment or an aftermarket, some of which claim to be better. I've found one company that offers the Mercruisers at about the same price as the aftermarket. Should I be safe and get the Mercruisers?

And one more question. There is no thermostat in the engine, which explains why the few times I ran it, it never got over about 100 degress. The service manual I have says a 160 degree thermostat, but some on the forum recommend a 130 degree. May be a dumb question, but which should I use? Thanks, Jody.

 

[achris]

Re: 4.3L Exhaust Manifolds & Thermostat

...with the batwing manifolds.

Terrible things!!!

I purchased my boat this past season and am trying to get it ready for Spring. I think I have the correct parts to convert to the 2 piece

Good choice...

(elbow tube and upper & lower bellows), and now need to purchase the manifolds & elbow risers. I can go with the Mercruiser OEM equipment or an aftermarket, some of which claim to be better. I've found one company that offers the Mercruisers at about the same price as the aftermarket. Should I be safe and get the Mercruisers?

So far I haven't had a problem with the genuine items. I have talked to a few companies who imported some Chinese made ones.... That lasted about 6 months. The castings were so thin that the corrosion killed them in less than that time...

And one more question. There is no thermostat in the engine, which explains why the few times I ran it, it never got over about 100 degress. The service manual I have says a 160 degree thermostat, but some on the forum recommend a 130 degree. May be a dumb question, but which should I use? Thanks, Jody.

Mercruiser recommends 160 degree, go with that.... The colder an engine the less efficient it is....

Chris........

 

[willxfs]

Re: 4.3L Exhaust Manifolds & Thermostat

River,
Keep us posted on what you buy. I have the same motor and need to replace the manifolds soon. Where did you find the mercs for a good price? Thanks.

 

[riverratjody]

Re: 4.3L Exhaust Manifolds & Thermostat

Thanks achris. And it looks like I was wrong about the manifolds I found being Mercruiser. The aftermarket brands, manifolds and risers, are around $500 and the Mercruiser are probably $300 more. I'm guess I'm going to go with the aftermarket brand, and try to pick one with the 2 or 3 year warranty. And thanks for the info on the correct thermostat.

 

[achris]

Re: 4.3L Exhaust Manifolds & Thermostat

Thanks achris. And it looks like I was wrong about the manifolds I found being Mercruiser. The aftermarket brands, manifolds and risers, are around $500 and the Mercruiser are probably $300 more. I'm guess I'm going to go with the aftermarket brand, and try to pick one with the 2 or 3 year warranty. And thanks for the info on the correct thermostat.

Just ensure the warranty covers consequential damage if they fail early... It could cost you a lot more than the savings on the manifolds if you have to have an engine rebuilt.

Chris..........