Oliver Super 55 Engine Compression no start ?

JM Outdoors

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I have a Oliver super 55 with a 4 cyl gas engine in it. I tried to start it is getting fuel too plugs, seems to have decent spark. I put a compression tester on it. Engine was cold obviously because it has not run yet. my readings on cyl 1 140psi cyl 2 95psi, cyl 3 70psi and cyl 4 140psi. The carb is a new re manned Marvel. It is pulling real hard at intake side of carb. Would compression like that stop the tractor from running? I feel it shouldn't I did take the valve cover off, while turning over everything seems to be moving. Any advice ? Thanks
 
Wet or dry compression test?

Disparity between cylinders like that is unacceptable if the test was carried out properly.

Some immediately-prior history would be good as well as condition of spark plugs and any adjustments carried out.

Could be any number of things preventing the engine from running - rings, bores, valves, valve clearances, timing, firing order, gasket leakage, to name most, I suppose.

I would guess that with two adjacent pots that much lower than the other pair, the fault is somehow connected.
 
Will it fire at all? I bought one in pieces last summer,overhauled it,towed it around the yard til we almost wore the tires off it. I should have looked up the firing order instead of assuming it would be 1-3-4-2. It's 1-2-4-3. When I switched to what it should be it started instantly with the atarter.
 
You say "getting fuel to the plugs", as in wet plugs? If wet dry the plugs, add a little oil to the cylinders thru the plug hole and try again. If the plugs were wet it is flooded. Make sure the timing is close to the proper setting. That compression won't keep it from starting. What number are the plugs?
 
Thanks for input guys. I do not have the history of this tractor. I purchased it for a 1000.00 with a wagner loader on it and a Henry backhoe attachment. from a guy that was selling it or just going to scrap it. I figured I would take the gamble as where it say the loader cylinders and backhoe were all holding pressure. The tractor has a cracked bellhousing. I don't think that would impact the starting. Hopefully we can figure this out. He is what I have done so far. this tractor was not in running condition upon purchase.
I drained gas out of tank.
I replaced the plugs Autolite 386.
I gapped the plugs accordingly to the manual.
The carb was a rusted mess so a Marvel re man carb brand new seals,float needles etc was installed. The fuel line was replaced and also a new sediment bowl.
The wiring was pretty tore up so I replaced batt cables, and new switch,and the wiring from switch to starter and coil wiring were replaced as well.
The coil is same one and the points and condensor looked relativly new upon inspection so I checked and gapped the points after cleaning them.
I replaced all spark plug wires and wire from coil to mag.
I checked the radiator fluid level it was normal and good in color green, i did not check with a fluid tester
I drained engine oil and filter. The oil did not smell like gas. Was not overfull and had no milky color, or metal shavings on plug. It looked like good used oil.
The plugs that were in it were Champion D16 but the store did not have them. They said Autolite 386 was a good cross referance. plugs gapped at .25
points gapped at .022 firing order 1243, cyl 1 start at front of tractor working toward cyl 4 at rear of engine closest to steering wheel.

The first couple times trying to start it , I was getting a puff or so of greyish smoke but not really wanting to run. The plugs did not seem to be getting gas, I took carb off again double checked the settings and the float. I believe the float might have been sticking.
The next few times still nothing but plugs were getting a little fuel on them but not allot as if fouled out.
compression test was done dry and rotated engine 5 times per cylinder. with the other two cylinders jumping up fast on the first and second crank and reaching 140 by 4th and staying at 140 for the 5th.
I rechecked cylinder two and three with a few squirts of engine oil.
cyl 2 reached a max of 115 and cyl 3 to 90psi. so it did improve but still not reaching the 140 of the others. I also sprayed down valves and valve guides with aerokroil basically pb blaster to see if maybe they are not moving as they should. By eye the 2 cyl rods seem to move possibly a bit less.
 
I did forget to add while looking over the valves it did seem as the a valve guide rod on the #1 looks to be pretty new a bit different than the others in color.
 
If your tractor is a 12 volt system the plugs could be set to .035 for a better spark. I run 386 plugs in mine set at .045. Make sure your timing is near to the proper setting. Compression, fuel, and spark at the right time and it will run.
 
Only four actual things to make any engine run.
Compression, Fuel, Spark and Spark at the proper time.(and place)

I only read that you checked three. I didn't read where you checked for the spark being at the proper time. Just spark is only half of the spark check. I have always thought of it as three major things with spark and timing being the same thing but it is obvious that it needs to be four or maybe five with proper firing order being the fifth. I had always thought of firing order and timing as part of assembly.
Just thoughts of a old man.
 
Thanks, Yes I guess I shouldn"t take for granted that the mag is in the correct spot. I just assumed that because I did not remove the arm or mag gear that it would of been TDC. I am going right back to the drawing board. I also noted one"s note that on the 386 plugs they gaped at .45 I can try that too. I am going to make sure it can jump a 1/4 as well. I only had the plug laying on frame and observed the spark looked normal. Also to note, would bad gaskets between the exhaust manifold and head cause any disturbances. I pulled the manifold off to check condition and make sure nothing was plugged.The gaskets or O Ring type seals are in rough shape. I plan on replacing. I do have a new points and condensor set so I might as well throw that it too just for some reassurance if they ever go bad then i can fall back on the ones I know are not brand new. Even with two cylinders low on compression I figured it would of started but just not ran that great.
 

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