Installing new exhaust manifolds and risers 50 GI

"Hello, I am in the process of

"Hello, I am in the process of installing new manifolds and risers to my 2001 Volvo Penta GI. This is being done for just maintenance. Just for grins, I checked the compression and got 185-190 in all but one. The number 2 cylinder was 175-180, which I think is acceptable.

\ Anyway, the surface on the head where the manifold attaches to the head is somewhat pitted on the surface to the center two cylinders on both heads.

I am using OEM manifolds and gaskets. Should I use some type of "copper coat" or permatex RTV on the gasket between the head and manifold? Also, the new riser gasket is metal. Should I use any thing on that gasket? I heard on another post not to.... What is the torque spec for both the risers and manifold?

Any other tips? What type of sealant or anti seize should I put on the bolts? I heard you are not suppose to use anti seize in marine applications due to dissimilar metal corrosion. Is that true?"

"I forgot to ask, what type of

"I forgot to ask, what type of sealant should I use for the brass plugs and nipples? Thanks!"

"Dwayne, I had the same proble

"Dwayne, I had the same problem with my 2002 5.0 gxi-a. When I removed the riser from the manifold the gasket appeared to be damaged. When I removed the manifold I also found the pitted surface on the head. The pitting was caused by the damaged gasket leaking water into the manifold. I checked with a local Volvo Penta mechanic, he told me the non metalic gasket was discontinued because of this problem. The new gaskets are metal like yours. The torque spec for the manifold - starting fron the center and working toward the ends, tighten the bolts to 27-35 nm or 20-26 ft-lb. the riser torque spec - 16-24 nm or 12-18 ft lbs."

"Larry, thank you. I am new t

"Larry, thank you. I am new to this forum and started loosing faith that I was going to get a response?

Did you replace the maifolds and risers yourself? Did you use any sealant on the gaskets like Copper Coat? I am picking my OEM up manifolds and riser tomorrow.

Thanks again!"

"Here are some pictures of the

"Here are some pictures of the parts "

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Dwayne I replaced the risers a

Dwayne I replaced the risers and manifolds myself. I did not use any sealant on the gaskets. I not sure but I think I used never seize on the bolts.

"Larry, The pictures of the ma

"Larry, The pictures of the manifolds and Risers are disturbing and they should go in the trash...New gaskets are metal and you should use new bolts without any additional sealing sealants..Torque all bolts crossed wise to specs...Flush out your system to stop this type of buildup and damage...Good luck"

"Yes, they are going in the tr

"Yes, they are going in the trash. I just picked up the new OEM risers and manifold today. BTW, this engine was flushed religiously after EVERY outing. I plan on using "salt terminator" to flush in the future.

The bolts looked fine, so I am not replacing them. I asked the dealer and they only recommended replacing them if the old ones were rusty."

"I finished replacing the rise

"I finished replacing the risers and manifolds and everything went fine.(Thank you) I noticed a significant amount of corrosion in the thermostat housing on the starboard side heater hose nipple (hose from thermostat to exhaust manifold). The engine runs fine and no signs of overheating. However, I can tell by feel that the starboard riser feel about 10-15 degrees hotter that the port side. I am going to replace the thermostat and clean the housing.

Any other ideas why one brand new riser would feel hotter than the other?

Any tips on replacing the thermostat?

Thanks!"

water pump R&R impeller an

water pump R&R impeller and check all hoses and flush the system

"Dwayne I would not worry abo

"Dwayne I would not worry about a 10 - 15 degree difference as long as the engine is running at the correct operating temperature. Mine runs at around 180. The difference in temperature could be the cooling water running through one side of the motor, heating up and then running thru the other side. Mine also runs hotter on one side at idle. Do you have fresh or salt water cooling? Have you ever changed the impeller housing? If the brass plate behind the impeller is worn it will cause a higher temperature at lower rpms."

"Larry. I have replaced the im

"Larry. I have replaced the impeller every year. Out of coincidence, I just replaced it tonight along with the thermostat (just for maintenance). I didn't get a chance to run it yet. I'll keep you posted.

Have a good one!"

"I lake tested the boat yester

"I lake tested the boat yesterday and everything went good. I still think the the port riser is a few degrees hotter than the other side, but nothing to worry about. The engine operating temp seems to be 170 degree. Thanks again!"