Volvo Penta after market exhaust manifold

[salamis]

Guys,
Has anyone actually fitted one of these after-market manifolds?
I am in the UK and a company here is selling tons of them as a replacement for the whole range and age of 4 cylinder VP AQ125-AQ151.
Mine is a AQ131B, and I am in the last throws of a rebuild.
I have bought one of these manifolds because they are so much less than the Volvo Penta genuin part number.
What troubles me is that the separation plate that is renound for failing is not in this manifold. There is no plate just a 1.5 inch deep shelf at the round opening.
I am rebuilding the engine because the number 4 exhaust port eroded away with salt water. Will this manifold make the water erode all cylinders.
Has anyone been using one of these for a season and there is nothing for me to worry about?

http://bpi.ebasicpower.com/mm5/merc...srch_pmkeywords=1&srch_pmdescrip=1&srch_mfg=1

http://www.iboats.com/Sierra_18_193...7018732--**********.401926856--view_id.222186

 

[captmello]

Re: Volvo Penta after market exhaust manifold

Welcome.

I haven't used the manifold your talking about. I'm not sure what your worried about. Your saying the inside of the manifold looks different?
I would guess there are a lot of those aftermarket manifolds out there right now working okay.

which brand did you buy.

 

[salamis]

Re: Volvo Penta after market exhaust manifold

Hi Captmello, and thanks for the welcome.

I bought the manifold from a company in the UK called Trickett Marine. the box it arrived in did not have a manufacturers name on it. All the after market manifolds seem to be the same casting which is a little different from the far more expensive genuin Volvo Penta one. The biggest problem with these 4 cylinder overhead cam engines is the ali head. They cannot take any amount of sea water without the end exhaust port being eaten away when the manifold rusts and breaks down. This must be why the new replacement for this engine was a push rod, cast iron head 3 litre.

The concern I have with the manifold is the difference in the internal geometry. But the guy who sold it to me might well be right and it will be fine. If there was a problem presumably he would be inundated with complaints.
Still best to ask before someone says 'you didn't fit one of those did you, everone is talking about them - they are rubbish'.

If they arn't then presumably it's not.