Installing Mercruiser Exhaust in Volvo Penta Setup for BBC 454
06-01-2019 | 11:20 AM
#1
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From: Spokane
Installing Mercruiser Exhaust in Volvo Penta Setup for BBC 454
I have a 1990 Wellcraft 26 ST with the VolvoPenta 454. Exhaust is stock and consist of the Volvo Penta cast exhaust manifolds, 6” riser and elbow.
Bad winterization and the manifolds cracked... My bad and lesson learned.
Help, due to the unique water design of the riser, I have to replace everything (just replacing the gasket from exhaust to riser was almost impossible to find - found 4 in Alaska from a dealer going out of business).
But-the manufacturer (I believe it’s GL) for Volvo Penta Exhaust is out of product and not expected to have more stock for another 3 to 4 months.... I don’t want to drop $3k on an aftermarket exhaust for a stock 454 at this point.
QUESTION: can I use the Mercruiser exhaust manifolds, 6” riser and elbow on a VolvoPenta setup? It appears to be the same height (18.5” from the exhaust centerline to the top of the elbow). I’ll have to fabricate a holder for the oil filter, but I don’t see any reason why I can’t use a Mercruiser exhaust??
A BBC 454 is a BBC 454.
Can anyone confirm that there’s not something I’m missing? Hate to order exhaust with a $200 shipping charge and have to then ship back.
Sure appreciate the help!
TJS
Bad winterization and the manifolds cracked... My bad and lesson learned.
Help, due to the unique water design of the riser, I have to replace everything (just replacing the gasket from exhaust to riser was almost impossible to find - found 4 in Alaska from a dealer going out of business).
But-the manufacturer (I believe it’s GL) for Volvo Penta Exhaust is out of product and not expected to have more stock for another 3 to 4 months.... I don’t want to drop $3k on an aftermarket exhaust for a stock 454 at this point.
QUESTION: can I use the Mercruiser exhaust manifolds, 6” riser and elbow on a VolvoPenta setup? It appears to be the same height (18.5” from the exhaust centerline to the top of the elbow). I’ll have to fabricate a holder for the oil filter, but I don’t see any reason why I can’t use a Mercruiser exhaust??
A BBC 454 is a BBC 454.
Can anyone confirm that there’s not something I’m missing? Hate to order exhaust with a $200 shipping charge and have to then ship back.
Sure appreciate the help!
TJS
06-01-2019 | 01:00 PM
#2
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Joined: Nov 2002
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From: PortRoyal Bermuda
I understand well the difficulty of being in a 'remote' location and you're asking the right questions . Besides the oil filter bracket is the existing exhaust also used for shift cable connections ? Out of curiosity what drive was Volvo using for this package back then ? The other question is , is it a through the lower unit exhaust system ? If it is , are the dump (down) locations the same for both setups so that they align with the exhaust tubes if you have through drive exhaust ?
This is a perfect question for BUP and hopefully the title of your thread will catch his eye .
This is a perfect question for BUP and hopefully the title of your thread will catch his eye .
06-01-2019 | 04:37 PM
#3
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From: Spokane
Thanks for your response! It’s a duoprop setup with through hull exhaust. In further researching, the GLM exhaust will work as the exhaust manifold, riser and elbow complete package, I believe**** is the same product code for either the mercruiser or VolvoPenta engine.
But, another problem is that I have a bbc 454 Mark IV block. The GLM exhaust state that it is available to 1991 engines.
QUESTION: A Mark IV and Mark V exhaust ports, heads are all interchangeable to my knowledge. Why would the GLM exhaust only be available for Mark V blocks? I’ll call GLM tomorrow and see if I can’t get an answer to that.
But, another problem is that I have a bbc 454 Mark IV block. The GLM exhaust state that it is available to 1991 engines.
QUESTION: A Mark IV and Mark V exhaust ports, heads are all interchangeable to my knowledge. Why would the GLM exhaust only be available for Mark V blocks? I’ll call GLM tomorrow and see if I can’t get an answer to that.
06-01-2019 | 07:57 PM
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From: Tampa Bay Area Florida/ North Miami Florida
2 things to watch out for. One I am not sure of . The other I am Pretty sure of. 1. Make sure the riser that makes the approx 90 is the same degree as your volvo. Some are like 10 degree and some are like 7 degree downturn. Thats usually with dry joint apps but just saying. 2 is make damn sure the long riser bolts are long enough and have plenty of threads going into the manifolds WHEN USING REOMTE OIL FILTER MOUNTS that are mounted to the risers. Sometimes you have to have custom lengths made. I like to have mine custom made as studs with extra threads on the top and bottom then cut a slit in the top with a dremel / cut off wheel so you can screw them in with a screwdriver. Put permatex avation gasket sealer on the threads and bottom them out in the manifolds. Then put a nut on the top side ans torque to spec.
Chris
Chris
