I bought new seals and removed-unbolted the crankshaft end caps and tapped out and in the the new seals using a large socket.
The top seal requires removal of the flywheel of course and the bottom the engine removal which was a lot of steps unbolting it and having 2 helpers lift the engine with a long 2x4 chained to the top of the flywheel.
OK, I thought that was how you did it. I believe ChampioNman posted earlier that replacing the seals required splitting the block, I also think this is the way it should be done. Also I think that 4 new seal bolts are required. If you got this done without any crankcase leaking, it's a miracle. This might be the cause of your idle and surging problems. I'm not saying that it is, but it's a good possibility. I don't know how to test for this, maybe omcforever, champioNman or Mr Seahorse does.Originally Posted by JIMTMCDANIELS
Did CSMS say anything about a jet change with his reeds? Some times an idiot will drill out a jet, I know that your jets number is correct, but have they been modified?
How did I replace the seals? I removed the flywheel and the crankshaft end cover. For the lower, took much more time unbolting the engine from the housing and attaching a chain to the flywheel and around a long 2x4 wood on top of the flywheel and having 2 helpers lift the engine out and onto the ground to access the bottom end cover and seal. Installed new seals with a large socket tapping.
I don't know if the old seals were leaking any but they probably were the originals...
Today I took the spark plugs out and using a short garden hose inserted into the carb throats 1 of the 4 at a time, I hand gloves rotated the flywheel and listened for the reed valves popping open actions. They all sounded the same.
Ok must be a cylinder(s) not producing power or firing at the wrong time.
I will do the individual cylinders power test by pulling the plug wires one at a time and watch for a cylinder that doesn't drop idle.
I did this early on and thought the were all producing now but I think I need to do this test again without getting shocked.
Even with rubber gloves and rubber handled pliers I did get some shock..
I have some nylon electrician fuse pliers coming from ebay. Maybe I'll try using a clothes pin just to get a head start.
It may be a cylinder is not getting fuel or too much. I've read that some omc carbs bottoms warp from over tightening the 4 bottom screws, not sure if my carbs are that type.
Also read that the idle jets pull fuel through the inner small diameter pickup tubes that are visible when the carb bottom is removed and to be sure these are clear which I have with carb spray but that also the rubber bottom gaskets seal around these brass tubes and can be installed wrong ...
Well things to check still haven't given up.
OK Jim, you can't give up but I can. Good luck
Have you put a timing light on this thing yet to see if your timing is correct and not getting a double fire?
Thankx for help!
Your altitude memo helped so much!
When I figure this out, it's going to be running great with those smaller high speed orifices, and not so smokey towing friends behind!
Last edited by JIMTMCDANIELS; 09-03-2018 at 07:42 PM.
Yes I have had a timing light on cylinder 1 but as stated previously, it won't idle down to the 6 deg, it does below like 13 deg.. even then, it coughs some or sneezes..
I have been a bit lazy and the daily time window to tinker with it and not annoy the neighbors is limited.
I did replace the tachometer that was erratic even with a new rectifier.
I still have not received in the mail the insulated fuse puller or spark strength-gap tester..
Today I used a wooden handle metal hammer and used it to pull the plug wires off and on while idling. I found that cylinders 1 & 4 with good plugs are Not producing any power, reduced idle..!
SO the best guess is their likely problems would be either no strong spark, sparking at the wrong time, not enough gas or too much or reed valves..
Well thanks for chatting and the support!
Splitting the engine open it is not needed, I had read it wasn't However the end cap is stuck on tight to remove. Use like WD40 and it must come out straight, any cocking will bind it and it's thick but fragile aluminun.
Then reinstalling, longer temporary bolts are needed to hold the bearing retainer inner plate in place while bringing-tapping in the end cap into place then once the end cap is installed enough, remove one at a time the temporary bolts while replacing them with the original bolts.
The long temp bolts I used weren't even the correct threads, I was able to just finger tight them to hold the plate in place long enough.
No I think that all went fine. The new improved seal even has like 3 sealing lips instead of 2.
Last edited by JIMTMCDANIELS; 09-05-2018 at 02:05 AM.
Anyone wonder why I gave up?
Last edited by 316jughead; 09-03-2018 at 08:57 PM.
Age and treachery will always overcome youth and skill !!
Since everything sounds perfect, id run some Johnson carb detuner through it and see what happens. Not going to hurt anything. Also check the roller cam gasket is still in tact and confirm the timing is about 28 degrees.
Thanks for the input!
I did get it idling much better and had a good run on the Lake. Now I'm looking forward getting through the rest of this year, my mother passed away in June.
Looking forward to next summer boating and getting more friends to go and figure out any secrets of the Lake and what we enjoy to do there.
I found my Main problem were the new spark plug wires with the spark plug end machine crimped and the coil end with a boot and spring that you assemble yourself, that came with the new e-bay "Sierra International" ignition coils I got to replace the original coils which really needed new plug wires and also had chips in their casing.
Even though the metal ends were all connected to the wires, I rechecked several times and good ohm meter reading, the electricity was erradically leaking out so not sparking the plugs.
It was very random where I'd have one cylinder not producing a drop in rpm at idle when using the hook on a wooden hammer to pull off the wire from the plug. Then it'd be a different cylinder or even two the next time I tried after fiddling.
So I bought on E-bay new "Marine Pro" 9" plug wires that already have machine crimped ends that appear to have superior insulation for the wiring.
Now all cylinders are firing well at idle so the rpm's are much higher although my idle screw must be turned all the way in, which of course increases the timing, set with the carbs not opening till the throttle is advanced from there.
The high idle screw setting I suppose may have to do with my altitude of 6,000 ft or another problem I have not solved.
Another problem I found is even warmed up, it seemed the high altitude idle jets were too lean as the rpm's would increase with spraying gas/oil mixture into the carb throats. So I put the original smaller(they let in less air) top jets and it seemed much better.
I did leave in the high altitude high speed jets and noticed when being pulled behind the boat, the fumes are much less than before.
Although I have another problem to figure out next year, seems it may be a fuel restriction the internet seems to say to check lines and filters although my lines and filters are new lol, in the water towards the end of the day, at full throttle, if I push past say 3,000 rpms, it would get to 4-5k and then the engine would die all the way down to have to restart. Even if I pulled back on the throttle. It would restart fine. Also after sitting with the engine off for say 30 min, the idle would be low without the warm up lever up and it seemed to take a while to get to where the idle was "warmed up". The water temp was 69 deg.
Anyhow thanks for your help guys
Last edited by JIMTMCDANIELS; 10-12-2018 at 04:24 PM.
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