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Trouble after rebuild

Are you still getting spark? If so shine the timing light at the marks and see if you can adjust the timing while someone cranks on the starter.
 
Search boatinfo library and then mercruiser #24 service manual. Go to page 291 and it shows the timing procedure. Follow it word for word and see how far you need to turn the distributor to achieve 8 degrees BTDC base timing. Make sure you lock the distributor down 25 Nm and recheck the timing is correct the do the shut down procedure disconnect the jumper then drop rpms to idle speed and stop the motor. Then restart and take the rpms up to around 1300 rpms and then see if she idles normally.
 
I followed the manual but it would not start when I put the jumper wire on. It would not start again after that when l removed the wire. I get spark noted by the timing light flashing and the engine trying to start. I'll try and see using the motoring method this morning
 
I think you were just way off on the base timing your basically resetting the computer inputs such as throttle position O-2 senser intake air temp and engine coolant temps and the computer just locks the timing so you can adjust the distributor and it runs on fixed values. Once you disconnect the jumper the computer then starts figuring stuff out that is why you adjust the timing at normal operating temp. As soon as you connected the jumper and turned the ignition on it retarded the timing so it would not start I`m hopeing once you get the base set everything else will just fall in line. Be sure and disconnect the throttle cable and adjust it if necessary after you get the timing set. If you messed with the throttle butterfly you will need to make sure it is correct as well.
 
Kimcrwbr1 and others,can't the distributer be turned clockwise or c/c until she fires up and idles,then adjust timing from there,does the computer prevent this from happening
 
Thank everyone

Its time for beer for me but not in a good way.

l managed to get the timing right eventually after cranking it many times and small adjustments etc. with jumper in then out then back in for final checks. The engine sounded very smooth and quiet.
Next we thought we would check how the advance was and then it happened, the sound of a bearing going. I am only thinking the worst ATM as you could imagine, I hope by some miraculous reason that the engine does not have to come out again.

I think I shall go away for a few days.................

ps Jonny what you suggested is what we did
 
bummer were you getting good oil pressure? Possible water circ pump, alternator, power steering pump? What drive do you have? How far did you need to turn the distributor to get the timing correct?
 
Well after l got the gauges working it showed good oil press
tried with the fan belt off to eliminate everything l could and noise still there
 
Is the drive full of gearoil?Hold a large screwdriver on the top of the drive and put your ear on the handle. If you pull the drive that will confirm if its the engine.
 
Silly question but which way is forward on the engine mounted cable as l don't have the remote control fitted
 
Another possibility is the starter is stuck on. Does the ignition switch spring back into the run position when you let off of the key?
 
Pull the coil wire off of the distributor and do a normal start and see if the starter keeps running when you let off the key? One of the black gearbox guys will know more about the shift cable if thats what your talking about.
 
Sorted the gearshift out. Pulled the leg off still the same. Tried the motor starter disengages

so its back to the shed and rip the engine out for a look at the bottom end
 
Found the big end bearing caps loose, I know I torqued them per the manual. Has anyone come across this before
 
From what I am seeing you torque 20 ft/lbs then add 55 degrees over angle for the connecting rods and they give you the option of 77 ft/lbs for the mains
 
Luckily my co worker was a auto mechanic and I could borrow his snap on torque wrench set. I found my craftsman was about 20% off. Expensive tools but you only buy it once.
 
So are you going to get the crank turned again to check for defects. Might be worth it at this stage to start out again with new bearings and have the crank ground under if necessary.
 
burls said:
Yep clearance was about 0.002 and still is. There is some marks on the journals but no big ones
Click to expand...

If you can feel the marks and you do not want to remove the crank and send it out for regrinding I would get some 1000 and 2000 grit wet sand paper and polish the journal as good as possible. I would also if you could replace the bearing and then re torque the cap to spec.

Make sure you use a good oil layer on the bearing surface before torqueing it and make sure everything is CLEAN!!

If the marks are smooth and they wont degrade the bearing surface you may be ok for a while....But don't expect a long life but you never know it could be fine and last a lifetime.

Don't think for a minute that every main and rod journal is as clean and smooth as the day it was ground after typical use over time........ I am sure many are scored but last a long time in that condition. The key is that the marks/scores are below the journal surface so they don't scratch the bearing surface.

There are the cross drilled oil holes and they do not lessen the life of the bearings any!!
 
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