4.3l exhaust manifolds

[Joshua Nichols]

Well I have finished with my deer hunting for the year and have come up on some spare money.. So as found out from some previous questions.. GLM exhaust manifolds are crap.. I need some replacements for my one leaking single piece.. So I was thinking of going with the osco brand... What yall think??
Here is a picture of the set up..

 

[Bondo]

Re: 4.3l exhaust manifolds

Ayuh,... So long as they ain't GLM or HGEs, go for it....

Osco is a good ole American company I believe...

 

[zbnutcase]

Re: 4.3l exhaust manifolds

Go for it! They are good products

 

[Lou C]

Re: 4.3l exhaust manifolds

If you had the one piece batwings like I do, that conversion kit is the best alternative....I put new bat wings on it back in 2004, they are still good and when I saw the prices start to go up I got another set to stash in the garage....when it's time, I'll bolt those on...
I do like not having the joint between the manifold and riser which can leak and corrode exhaust valves, but for sure they are expensive and must have been a lot harder to cast...

 

[rynosback]

Re: 4.3l exhaust manifolds

I had a question about them same thing and this was what was said in my thread.

I have a 2002 Crownline 202 bowrider with the Volvo 4.3L GXI engine(fuel injected). The boat is run in brackish water. The boat started to over heat a little at the end of this season and I have determined that the exhaust manifolds are clogged. So I am happy with how long the OE manifolds lasted. So these are my questions

1. Should or do I need to replace the risers at the same time?

2. I was thinking of going after market because of the cost difference, is there manufacture that is recommend over any others?

3.Is there a shop manual on line that I can down load for free? I need the torque specs.

Thanks for your input and knowledge.

1. Yes

2. Osco

3. I just replaced them on my VP 5.0. Torque was 12-18 on the risers and 20-26 on the manifolds.

It was the first time I had done this and it was a much easier job than I expected. Get a longer bolt and cut the head off to make getting manifolds on easier.

 

[Joshua Nichols]

Re: 4.3l exhaust manifolds

If you had the one piece batwings like I do, that conversion kit is the best alternative....I put new bat wings on it back in 2004, they are still good and when I saw the prices start to go up I got another set to stash in the garage....when it's time, I'll bolt those on...
I do like not having the joint between the manifold and riser which can leak and corrode exhaust valves, but for sure they are expensive and must have been a lot harder to cast...

Yeah I got the wing suckers.. Would love to land some new ones but not going to happen.. The ones on my tub I am pretty sure are original gear.. That's some long time use.. Hope the aftermarket stuff can hang.. I only run fresh water anyhow..

 

[HorizonblueDK]

Re: 4.3l exhaust manifolds

These are some fine replacement for the Mercruiser one-piece manifolds. Stainless steel, expensive as hell.

http://www.hitekmarine.com.au/mercruiser-chev.htm

They also make a replacement for the standard V6 manifolds, polished, very nice. All are made in one piece, so no leaks.

If the engine is flushed after each trip(so there is only freshwater in the manifolds) I don't think you will ever need new manifolds again.

 

[Joshua Nichols]

Re: 4.3l exhaust manifolds

They make some fine looking stuff.. Didn't even check out the price.. Hell the ones I am buying now cost more than I paid for the boat... The price of shipping from Australia and the sky high price most stainless stuff I can buy another rig with a V8 instead of the 6