mxz800

i took the risers off my boat tonight (99 7.4 mag efi) i could see where the riser gasket had been leaking. Is there a special gasket i should put back on there or are they all the same. manifolds werent clogged but had some rusty scaling goin on inside. didnt want to take the manifold off the bolt heads started chewing off holding them onto the heads. is there anything thing i should do to the manifolds and risers while i have them off to clean them out?? also is there a reason merc used that cheap plastic elbow in the bottom off the manifold and not a brass or copper one?? water was leaking from there so those elbows will be replaced also.


Thanx Rob

Pwrbt33

iTrader: (2)

mxz800,
Mercury used the plastic elbows to aid in draining the water system down. Now when we replace the manifolds, they send an old style brass elbow with no drain. This way there are no leaks and stains in the bilge. The gasket you should use to replace your riser gasket is a part #27-863724. This gasket is a foil covered gasket. You will want to make sure everything is very dry and torque the risers to 28-30 ft lbs.after running the engine for a few hours you should check the torque again. If you have they ability to you may want to have the risers belt sanded to make sure they are flat.

If you have any other questions feel free to email or call me at the shop.

Pwrbt33- John S.
Offshore Performance
1-877-GOFAST1

mxz800

thanx John i will be over some time this week to get the gaskets and drop in to say thanks!