Re: Help, smokey exhaust 502 MPI
 

I always lke to collect as much info as possible when trouble shooting. Especially when (as in this case) the symptoms can indicate serious problems.

I agree that in this case, a flow restriction or pump problem is the more likely cause, but if it were me, I would like to rule out a bad head gasket or valve problem (reversion) as the cause. I would also like to know that the steaming has not damaged (rusted) any valve seats. While this may not directly locate the problem, I will now have a sense of the scope of the problem, and most importantly that engine damage is contained.

Dave

Re: Help, smokey exhaust 502 MPI
 

Well, I put the hand into the exhaust water coming out of the pipes. The starboard is about 110 and the port about 70 at idle and operating temperature. It is logical that the side that flows the least water is warmer and steams the most. It should be the same amount of heat that needs to be cooled away on both sides.

If it is not a leak in the manifolds or risers, I am beginning to think that I, in addition to the uneven distribution, may have a leak in the hose down in the drive, giving too little water flow when coming up on plane. It steams A LOT after a high speed run. I will try to check that in the weekend.

Re: Help, smokey exhaust 502 MPI
 

Thank you all for the input. I will do some further trouble shooting and see what I come up with.

Mats

Re: Help, smokey exhaust 502 MPI
 

I also have 502 magnums that have always steamed much more from the port side than the starboard. Cooler air temperatures always make it worse.

Re: Help, smokey exhaust 502 MPI
 

Hi. i have now done some further trouble shooting and it is clear that there is a leak on the suction side of the waterpump. When getting up on plane, the amount of cooling water coming out of the exhaust pipes is reduced to a fraction of what it is when idling. What can be leaking, besides the little hose between the gimbal housing and the bellhousing? the O-ring between the outdrive and the bell housing?l