cracked head and impellar issue

[clinton]

Well i replaced my fuel pump yesterday and i no longer have that issue.

ok, before i get too far. i have a 1999 21v' riders edition with the 350 MAG MPI Ski.

the issues i still have, now that the engine will start, is the port side head has a 3 inch crack and it spews water into the engine compartment. there is no froth in the oil on the dipstick so i think it is only an external crack. two questions here: can i use an automotive head? Do i need to replace both heads or can i replace just the port side?

I did take it out to the lake yesterday to get in a quick set before any parts arrived and have two more issues to address.

in the last few years i have gone through probably 2 to 3 serp belts per year. after reading some posts it appears i should check the flywheel bearings, i am unsure as how to do this... I do have a new impellar housing on order and i may still have an alignment issue, again i am not sure how to check this other than trying to 'eye it up'

for about a year and a half i have had a problem with the impellar reversing when the engine has difficulting starting and i will not turn back over with out me dis-assmebling the housing and manually reversing it back to normal. (could this be related to the cracked head???)

i have had excessise water in the bilge during this time frame. though i never noticed water from the head until this spring at initial start up after replacing the fuel pump. (I drained all 5 plugs in the fall and filled with 2 gallons RV fluid by turning over the motor though it did not start.)

the other problem is a charging issue but i think we solved that by cleaning off the terminal and snugging up the battery connections. Battery was dead so hard to test.

[whitlock87]

I believe the heads are the same (same valves and seats)
If you replace the one, replace them both as you want even pressure on all eight cylinders. Besides, it not that much more works to replace them both.
Not sure how the flywheel bearing has anything to do with the belts, as the flywheel is in the bell-housing (back of engine) and the belts are located on the front. I would check to see if some how you bent one of the pulleys, as it might have been stepped on. If you going to replace the bearings on the crank, (main bearings) you will need to pull the engine. If I were going to pull the engine, I would think about rebuild the whole thing.
How is the compression on the cylinders?

[boatwakes]

Clinton, if you want, you only have to replace the one head. Be sure to look under the valve cover at the casting number of that head so you get the same one for replacement. Drain the block, remove all the ancilliary crap and loosen the head bolts in opposite order of tightening sequence. You'll need thread sealant for the head bolts when you replace the head and it's always a good idea to clean up the block threads with a tap before installation.
As for the flywheel bearings, someone is pulling your chain, there are no such things. Belt life is directly related to the pulleys, either through alignment or pulley bearings. Double check the adjustment pulley bracket is not bent and the idler pulley bracket is not bent. Both are up high on the face of the engine and you should also check the bearings in them by spinning the pulley. Also make sure the bracket for the raw water pump is not bent or tweeked.
And the impeller: I've seen several engines have that same reversing issue with a hard to start or no start condition. I've always been able to remove the belt and turn it back the correct direction by hand but if the engine is running and starts consistantly now, that issue should be gone. A final solution would be the silicone impeller from globe manufacturing.

[clinton]

sounds great, i have one new head on its way. thank you for all the info. two people have offered to help with the swap over so i am confident we will be back on the water this weekend. I like the silicone impellar idea though i may have a bent bracket somewhere because the belt seems tight closest to the engine with more play on the other side one inch away. I also ordered a new impellar housing though as it sounds may not solve my problem, there is a chuck of metal missing off one of the mounting threads so i might as well swap it out too just in case.

[boatwakes]

Also!!!!!! Use only a marine head gasket either from mercruiser or Fel-pro, no automotive head gaskets as they will fail from the outside in!!!!!

[clinton]

got it. thanks.

[clinton]

the new head is in and the the intake and distributer as well.

I cannot find markings on my engine so that i can find TDC to adjust my valves. i am so close.

anyone know how to find TDC with out the factory supplied engine markings. or maybe i am blind and cannot find them.

help, please.

[boatwakes]

There is a hash on the balancer but it's painted black like everything else, feel for it with your finger nail first. Rotate the engine (rightey tightey) with the 5/8" hex head crank bolt till it lines up with the timing tab then mark it with a silver permanent marker for timing purposes. Timing tab is located on the starboard(right) side of the boat on the v-drive models. You're also gonna hafta time the engine afterwards, do you have the scan tool or dtc connector with the properly shorted wires? If not, there's a thread here I was just helping someone with last week.

[clinton]

no, i don't have the tool. i can see the has mark, my problem is that the timing tab has rusted off. looks like i'll be changing the timing cover unless someone here has an idea on how to time an engine with out the timing tab.

[clinton]

i was able to time the engine at a friends house by hooking up a vacuum gauge and when it maxed out we were set (i think mine was 21 psi)

with the new raw water imellar housing the impellar has not flipped on me, i think that is fixed.

I also installed two new pulleys and there is still a squeal so i must be the water pump. ordering tonight.

The head swap out took me an entire weekend but it was really not too bad apart from the learning curve on timing an engine and adjusting the valve.

i also have a surf related fuel issue that i will ask about in a new thread.

[clinton]

let's talk about a mystery sqeal in the engine which appears to have something to do with the serp belt.

I have replaced, the alternator (2 years ago), pulleys, water pump and raw water imellar housing within the last week. I think i am golden but there is still a grinding noise. I put a stethoscope on all of the above and they sound normal. i did the same on the heads... could this be casused from the crank?

any other ideas?

[bigdaddy_houseboater]

I think those are stock 194 heads... If the casting numbers arent exactly the same, it's certainly ok to get a same-year head to replace it. I would talk to a local engine builder first. They arent really "marine" heads per se.
From the sound of it, you have more issues than just the head. There are no "flywheel bearings". The only bearings are the mains on the crank, and if you have issues with those, it's rebuild time. I have built several 350-block motors for boats. It's not a tough gig, if you care to do it. Thats a very simple engine to rebuild. If you cracked a head, then the rest of the engine saw the same heat....
Have you run a compression test on all cylinders yet? Also, when you had the head off, did you take pics of the piston tops?

[clinton]

i replaced the head with a 906 (i think is the #)

my fear is that is could be crank bearings, after tearing the engine down to swap out the head a rebuild does not sound like too much more to learn.

Cylinders tested at 95 to 105

I did not take pictures of the pistons, they looked as if there were no flaws, chucks or burns on them so i was not worried about it. all the cylinder sleeves were just as clean.

I will run it up to a mechanic friend of mine's house to get his professional opinion. though a rebuilt engine would be nice i am certainly not liking the idea of putting even more money and time into her. I already have $2k into it this year. At least i don't have a boat payment.