I managed to find a Johnson V4 140 on ebay
I was told it had a problem regarding no spark possibly CDi fault.
The guy also said it had OK compression but couldn't mind what it was.
One thing to take into consideration i stay in Scotland and there are no dealers near me and its VERY RARE to get hold of a 140 mostly all the motors are 30/40 hp fishing engines.
Will clean out and fit new carb kits
Check compression
Check spark gap Find and fix fault.
Drain lower unit and refill with new oil.
Is there anything else that should be done ?
I have a few spare CDi units and coils so that is not a problem to change over.
So hopefully get her running in a day or two
in any event a new impeller is in order and the gearcase needs check for water in the oil ... new oil won't help if water is getting in 2 minutes after
Once you get above list completed, you should replace impeller/water pump, rebuild fuel pumps, and possible replace all fuel lines. They don't last forever and ethanol destroys all these parts.
Parts should be available from online retailers or BRP directly. You just need to find one that will ship to Scotland.
Compression test done not good news.
#1 125 psi
#3 110 psi
#2 100 psi
#4 75 psi
I will put some marvel mystery oil in the pots and leave for a few hours see if that helps.
If not it will be a rebuild probably the quickest rebuild on here.
No surprise at all.-------See the broken rings all the time !!----Post some pictures with heads off.----Now you know why it was for sale needing a " tune up " and some tender care.
Is it OK if i start a new thread on the rebuild of the carbs. i will do a proper tutorial on how to refurbish V4s carbs
Might even be a sticky ??? You never know.
It wont take away from the rebuild
Is it worth a try ????
Have 4 new wiseco piston kits, new needle rollers, new crankshaft seals ect i was intending to build a motor over the summer.
But if this does need a rebuild it will be done this week. I goto the loch on Sunday to put the boat in for the summer.
Hopefully the marvel works never seen it before, i had to get it shipped to the UK.
?----Take the heads off to look for damage.-----Hard to believe that folks have difficulty in accepting the fault with these crossflow motors.----I believe the damage will be obvious.----Perhaps take bypass covers off to inspect pistons / rings as the wee gaskets are cheaper / easier to make..
I have all the gasket so no worries about tearing it down. Will take the heads off and take it from there. Was hoping to losen a stuck ring with the oil. More like praying it would work.
Any way stay tuned this may go as far as Tags rebuild.
Hopefully not though !
Its 3pm Monday lets see how long it takes to get her running.
Will be asking a lot of questions as i go so raceone please help me out if you can, you have probably forgotten more than i know about outboards.
Cheers Andy
Today has been a waste of time. Haven't had a chance to get to the motor bar pour some Marvels down the plug hole.
Next chance i get will be Wednesday. Give time for the oil to work. I am not holding out much hope of this releasing the stuck ring but you never know. Plan is try the comp test again on Wednesday. If it stays as is the heads will be off and more than likely the power head will be striped. Fit new crank seals, pistons and needle bearings, Might as well make a new wiring loom whilst its in bits.Then attack the lower unit.
That will give 5 days to get her turned round. I have a factory manual to help but if i ask a question on here, i have to wait at least 5 hours due to the time difference
Wish me luck lol
Andy
Cheers Tag i have already got them soaked in release oil. I hope i dont need to strip her but if i do hopefully no stuck bolts.
Plenty release oil and heat available. I hope we get some heat out side as well. We have been hit with a cold front from Siberia that last week or so. My home town was cut off for a few days with the snow.
We never get snow as the temp from the North Sea usually keeps it at bay. The last time it snowed here was in 2010
So it must be bad this year heyho
Just my luck
I managed to get 20 min to spend on the motor. Re done the compression test. Still at 70psi so the night soak in Marvel done nothing.
I them pulled the heads and found the cylinder scored as in the pics.
I think its a ring strike but not sure.
What would cause the piston to melt/mis shape in this way ???
Could it been too lean ???
So tomorrow i will try and get the power head off, if i can then it will be an hours drive to a machine shop and get there verdict on it.