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| FORD LEHMAN 80HP WORM DRIVE |
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Message |
    
JENNY GREEN
New member
Username: jenny_green
Post Number: 1
Registered: 10-2009
| | Posted on Thursday, October 15, 2009 - 06:59 pm: | 
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ENGINE HAS CEASED 4 TIMES DUE TO NO OIL PUMPING THROUGH MOTOR, OIL PUMP HAS BEEN CHECKED AND FOUND OK. COULD IT BE THE WORM DRIVE CAUSING THIS PROBLEM ? |
Fred Frog
Member
Username: lilypad
Post Number: 68
Registered: 01-2008
| | Posted on Thursday, October 15, 2009 - 07:16 pm: |
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Without any information about when and how it happens you won't get any help. Tell us when it happens, after running 2 hours or right after startup? What type oil? How much oil? Is it possible that the return holes in the head are plugged and the oil is not returning to the pan? Was any work done to the engine prior to the problem? Have you had the engine for a long time or did you just get it? Did it run normally and then just start this behavior? What is the oil pressure when it's running? Does the engine use oil?
Here's an analogy. My car is wet in the mornings. Does my garden hose have a leak in it?
Give us some information and we'll give you some things to look at. |
JENNY GREEN
New member
Username: jenny_green
Post Number: 2
Registered: 10-2009
| | Posted on Thursday, October 15, 2009 - 09:11 pm: |
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Thank you fred, this is the first time i have done this. Our motor was working fine when we first brought our yatch in 2004. it didnt burn oil and we never had any problems with it.in dec 2005 it ceased due to the drive damper and fly wheel becoming jammed due to a broken spring. the motor sat with the head off of it for about 6mth in the engine bay..there was nothing wrong with the pistons we decided to rebuild the motor since we had to pull the motor out and due to the cockpit of the boat we didnt want to have to do it again in the future..the things that we have done up to date..1/on the first rebuild we put new pistons and rings new bearings big ends and mains in.the block was honed on the boat.when we first started the motor it seemed to run fine for the first 5min.then it over heated and ceased, running time approx. 10min. idled at 700rpm was not reved over 1000rpm.. on dissassembly of the motor found big end bearing numba 2 welded itself to the crankshaf. replaced all the bearings again. motor assembled again. motor started and the same thing happened again motor ran for approx. 15min. this time it was big end bearing numba 3 as before had welded itself to the cranckshaft.this bearing was replaced only. no other bearing was replaced. motor was assemembled again and started again motor only ran for approx, 15 / 20min. again the motor overheated and ceased again.motor dissasembled again and found bearing 2 was as before . when we pulled the motor out we replaced bearing numba 2 only . we have cleaned out all ports in the block and when the motor was started we unscrewed the oil filter to see if there was oil pressure there was pressure but dont know if it was air pressure.?? we bought a new oil sender and a new oil pressure gauge and had it installed but have found out since then that the guy who installed it stuffed up cause it goes straight off the gauge. " there has been a few men that have ripped me off serverly." on this last rebuild replaced only the dameged bearing big end numba 2 . When we assembled the motor this time cranckshaft ports all checked and cleared all and any hole i could fined was checked for blockages none were found, we replaced the heat exchange (water) and when stated the motor again this last time only ran for less than 5 min, then it ceased again. wont turn over .the only difference was that there was no squeal this time on all the other ocasions i have heard a squeal from the motor .and also the timming cover was on each occasion ther has been no oil or any evidence of any oil inside the front timming cover plate i hope this enlightenes you a bit to my problem. |
Fred Frog
Member
Username: lilypad
Post Number: 69
Registered: 01-2008
| | Posted on Thursday, October 15, 2009 - 10:10 pm: |
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Ok, let's see what we can do. Your bearings are seizing from no oil. Sometimes bearings are put in upside down and the oil hole doesn't lube the cylinder but that doesn't appear to be the case here.
So, if you'll pardon my simplification, because you might have already done some of these things, here's what I'd do.
You have to open up the bottom of the engine again. Replace ALL bearings, yes again. They've all been run without oil. It is expensive, but needs to be done. Have the crank checked and polished. If you've seized two bearings on one journal and one on another it simply can't be clean and smooth enough to be reliable. (yes, mains and rods) When you're assembling check the clearances with (brain fart, comes in a paper sleeve with the string like substance inside. Put a small piece in the rod bearing, tighten everything up to spec then take the cap off and measure how wide the string like piece squished to, to get the bearing clearance) Put lots of assembly lube on all bearing surfaces. In the old days we just used oil or STP, the assembly lube is much better.
If you never had the camshaft out yet, you may need to replace those bearings too. They don't have nearly the pressure on them that the rods do, but they sat for at least 6 months with no lube and then have run since then with no lube. Your call as to whether to do them or take a chance.
I would replace the oil pump. Make double sure it is the right one. If it was replaced before.... are we sure it was the correct replacement? There is a pin at the top where the gear is connected to the shaft, make sure it is in place and not broken. Clean the pickup tube and screen. When you're done, you should be able to put it on grandmas thanksgiving table. (cleanliness is important) PRIME THE PUMP. Put the pickup in a clean can of oil and rotate the shaft so it picks up oil and pumps it out. Make sure when installing it, that it is engaging the cam drive. Make sure the pickup tube is in place and tight.
Remember too about burping the coolant system. There should be a petcock in the front, on top of the exhaust manifold. Open it and pour the coolant in slowly allowing air to escape. SLOWLY pour the coolant in. These engines air lock very easily.
Button everything up again, put in 12 quarts of oil and give it a spin. If I was nervous, I might even close the seawater inlet valve and crank the engine with the shutoff button pushed (or cable pulled) and let the engine pump oil without firing.
You should be ready to go after this. Remember, boating is a lot of fun. Right now it's a pain, but better days are coming. Please write back if you have more questions.
K |
Fred Frog
Member
Username: lilypad
Post Number: 70
Registered: 01-2008
| | Posted on Thursday, October 15, 2009 - 10:13 pm: |
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Oops, forgot you have a 4 cylinder so the oil drive isn't between 4 and 5. And you'll only use 8 quarts of oil.
K |
JENNY GREEN
New member
Username: jenny_green
Post Number: 3
Registered: 10-2009
| | Posted on Thursday, October 15, 2009 - 10:23 pm: |
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thanks fred. i have had the crankshaft and the oil pump checked by a qualified bloke done the clearances with flexi gauge (brain fart) and did the burping of the coolant system but i will take your advice and take the camshaft out and replace them bearings also ...thanks again |
Doug Tremble
Member
Username: shakey
Post Number: 44
Registered: 08-2009
| | Posted on Friday, October 16, 2009 - 07:06 am: |
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Hi Jenny,
Seems we are both having gremlin problems just spent 1/2 hr on reply then dispatched it to infinity! so now i have decide to go for the bull's eye; due to grank flywheel lock up when drive plate failed the grank either 1. bent. 2.cracked. 3.caused exessive end float 4. once had a engine with a direct coupled P.T.O .crack a grank causing exactly same symtoms.Fred has some good info posted; double check all measurements take nothing for granted. Good Luck. |
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