Predator and h50 won't turn with spark plug in

Cornishrooster

Cornishrooster

New Member
#1
#1
Hey all,

I hope some day I can help people here as much as everyone has helped me. I'm not sure how to search this one really. Both of these engines won't turn when the spark plug is in. On the predator I have the valves both set at .004. I don't know of a way, if any, to set the valves on an h50 tec. What would cause the engine to not release the compression? The timing is matched correctly I believe. Do the valves have to be in a certain position when I match the timing holes on the cam and the crank?

Thanks
Mike
 
Cornishrooster

Cornishrooster

New Member
#3
#3
buckeye said:
TDC, I believe. Wait for other responces to be sure. :thumbsup:
Click to expand...
Okay I just assumed that when you lined up the two timing holes that it would automatically be there. I was reading in the tecumseh technicians handbook and the valves aren't identical. One of them is nonmagnetic and that one is installed in the exhaust port. I just threw them both in since they were unmarked. That would be nice if that was the problem.... still haven't taken the roper on her maiden yet!

Thanks! :thumbsup:
Mike
 
Cornishrooster

Cornishrooster

New Member
#5
#5
It's the plug that came with the motor. It has the same effect even if the plug is only half way screwed in. Must be a compression release problem I think. What's a ya think?
 
minibikin'

minibikin'

Sho-nuff
#6
#6
Well, the h50 doesn't use a release like the clones. It's done through the camshaft holding the valve open to bleed off static compression. So, if it doesn't turn over there's more to the story. The clone/predator had adjustable valve train and its been discussed before on how to set them properly. Searching that forum should get you what you need.
 
Cornishrooster

Cornishrooster

New Member
#7
#7
minibikin' said:
Well, the h50 doesn't use a release like the clones. It's done through the camshaft holding the valve open to bleed off static compression. So, if it doesn't turn over there's more to the story. The clone/predator had adjustable valve train and its been discussed before on how to set them properly. Searching that forum should get you what you need.
Click to expand...
Yeah I've searched a lot before I even started this thread. Not one thread has anything to do with the engine being hard to turn over with a spark plug in. Anyway I just order some billet parts and some new springs. Hopefully when I take the whole engine apart and put it back together it'll work the way it's supposed to..... not likely though since I'm the one doing it.

Mike
 
P

predator

New Member
#8
#8
you might have set the clearance after the exhaust valve closed, you want to set it right after the intake valve closes at top of stroke on the predator.
 
P

predator

New Member
#10
#10
It happend to me when i adjusted them the exhaust valve closed and the piston was at the top, but i went another stroke and then they were really lose. So when the intake valve closed and piston was at top thats when i adjusted the valves and it seemed to make a differance.
 
Y

youngengines

New Member
#11
#11
On the Predator it sounds like too much exhaust lash. Just turn the engine over checking lash as you go, find the spot where the lash is the most and set it as close to zero as possible with the engine COLD. (lash grows as the engine gets hot).I turn it past max lift, till it closes, then check it, then turn it past the compression release, check again.
 
creia

creia

#12
#12
Hello Mike,
On the Predator, I'm trying to get a better understanding here...
Was the engine purchased NEW in the box, and did the engine EVER run correctly? Or were mods/upgrades done to it THEN it would not run right? (If so, what mods/upgrades were done?)
Michael
 
Cornishrooster

Cornishrooster

New Member
#13
#13
Hey there
It was new. It sat around for awhile since I was trying to fix the h50. When I finally got the mikuni hooked up to the predator I started it and it fired up on the first pull. I thought maybe I could leave the governor in with the Mikuni but I was wrong as usual. I couldn't remember how to put the stock carb on so I removed the governor so I could use the Mikuni. I ordered billet parts and heavier springs but while I'm waiting for those to arrive I buttoned up the engine and tried to start it. It won't start. I took off the valve cover and reset the lash to .004 on both. Still wont start. I can tell you the valve gasket is soaked in oil and the spark plug smells like gas. Oh and I also removed the oil sensor.

Thanks for the help.
Mike
 
creia

creia

#14
#14
O.K., that's helpful. It sounds then, that the engine was never ran (new, out of the box) with the STOCK carb, correct? It sounds like it COULD have had problems from the factory (some are just "duds"- been there, done that). Can you put all of the stock equipment back on and try running it? If still no go, I would go back to HF and exchange it (assuming that it is complete, no damage, with no internal modifications), and THIS time, try running it stock FIRST, before doing any mods/upgrades.
Michael
 
Last edited:
Cornishrooster

Cornishrooster

New Member
#15
#15
Okay. I did buy the warranty but they won't take it back unless I put it back together. Unfortunately I haven't the slightest clue how to do that. Hahaha. I started to try...
Is there a boneheads guide to predator reassembly?
 
You must log in or register to reply here.
Top