Robin Subaru Engine Problems With Solutions

[BobRip]

the sparkplug doesnt really have the black soot on it so it isnt a oil burner.
it just has to weak of a spark on the one side and the coils are good.

Could it be a bad ignition wire? I think the wires travel with the coil.

 

[vince93x]

i have a robin 7hp overhead cam engine that has a problem, it turns over when u try to pull start it but then it stops and wont move, but if u take the spark plug out it will turn over with no problem, i took off the valve cover and evrything looks and seems to work just fine so i took off the crankcase cover but evrything in there seems fine. what could cause this?

 

[BobRip]

i have a robin 7hp overhead cam engine that has a problem, it turns over when u try to pull start it but then it stops and wont move, but if u take the spark plug out it will turn over with no problem, i took off the valve cover and evrything looks and seems to work just fine so i took off the crankcase cover but evrything in there seems fine. what could cause this?

Could you have fluid in the combustion chamber? Pull the plug and try turning it over. If fluid comes out, that's a problem.

 

[J_J]

Hydraulic lock might do that. Too much fluid in the crankcase.

I know about this, as my float was leaking, didn't know it at that time, and I tried to start the engine as normal, and when I pulled the rope, it pulled a little and then locked up. Drained the oil and gas, refilled the crankcase, and everything worked after that. I now shut off the gas lever to prevent this from happening again.

If water can get in the engine it will do the same thing.

If an engine has been sitting outside for a while, check the oil level.

Cover the engine or machine if possible.

 

[Gator6x4]

i have a robin 7hp overhead cam engine that has a problem, it turns over when u try to pull start it but then it stops and wont move, but if u take the spark plug out it will turn over with no problem, i took off the valve cover and evrything looks and seems to work just fine so i took off the crankcase cover but evrything in there seems fine. what could cause this?

The wrong spark plug is installed. The plug is being screwed down into the combustion chamber and the piston is hitting the plug at the top of it's stroke. Install a plug with a shorter reach into the combustion chamber.

 

[J_J]

Reference the above post, are you using a factory plug. Shine a light in the cyl and see if there are any markings on the cyl.

Look at the plug and see if the tip is bent, or smashed.

The question is, why would you install a plug longer than normal. Is it a direct replace for the factory plug.

 

[vince93x]

spark plug is the right one, and all the valves/cylinder is good. but i cant find anywhere what the head bolt torque specs are, does anyone know?

 

[jaquetarr]

After the engine starts acting up you might try running it on propane fed into the air intake.Careful not to feed too much & over rev. This would let you know if the problem is fuel related or electrical related.

As to engine locking up & you've tried the items mentioned, How about a valve problem?
tim

 

[kmaz]

well my 425 with 240 hrs on robin engine died maybe a couple months ago. For the first time of ownership i was extremely dissapointed and to be honest i didnt know what i was going to do. This does seem dramatic now but until this happened i never once wished id shopped at the kabota dealer down the road. It now sat in the middle of a field. After running for maybe 3 minutes with mower it began to bog down as if clogged with heavy wet grass i imediately raised mower slightly to alleviate the load when it died. Visually i could detect nothing wrong and after several attempts at restarting came up to the house to get on tractorbynet. I was not optimistic but id read posts in the past regarding valves and rocker arms so searched everything i could. Next day went out removed valve covers and spark plugs and turned her over and noticed one of the valves was not operating. Using robins terms , what they call the " pivot bolt" lossened up and in turn provided enough play for the pushrod to unseat from the rocker arm!!! I couldnt believe it... could the fix be this easy? I would of thought something would of bent or broke but it seemed fine. I temporarilly tightened everything back up hopeing it would start so i could get it to the garage. I couldnt believe when it started!!!
I have since ordered new parts incase something was bent and gaskets , adjusted to specs and she runs like a top now....once again smitten with my pt.
one tip, when adjusting valves, to find TDC, i removed sparkplugs and used a screwdriver to rotate flywheel through back of tub visually lining up mark on flywheel to center of coresponding cylinder

 

[Marks481]

one tip, when adjusting valves, to find TDC, i removed sparkplugs and used a screwdriver to rotate flywheel through back of tub visually lining up mark on flywheel to center of coresponding cylinder

Please provide a bit more info about the "back of the tub" statement. Last time I did this, I found TDC by removing the spark plugs, putting a straw in one of the spark plug holes, and goosing the ignition switch until I managed to get to TDC.

How did the screwdriver thing work? The fan entrence is in the back of my tub, I don't see anything a scwdriver could engage.