0 compression? Adjust valves?

davisford · Jul 28, 2015

Ok here is a weird thing. I am trying to get my tractor to start after I had to replace a piston. It won't start.

Anyway did a compression test today and it showed 0 on all 4 cylinders????? However I can feel compression when I hold my thumb over the plug hole, so there is something there. I will try again tomorrow with a new compression gauge. Anyone see this before or have any idea how an engine can show 0?!?!?!

Also- my rotor has a lot of play in it, Not the distributor, but the rotor itself. Is the rotor a common rotor used on other engines that I should be able to find at a local store?

Thanks

Tractor is 660 with gas engine

Bern · Jul 28, 2015

If you can feel something with your thumb, then you have more than 0 PSI. Try a different gauge.

Larry NCKS · Jul 29, 2015

(quoted from post at 23:13:24 07/28/15)

Ditto what Bern said.

Now to problem # 2. If it's what I think it is, a new rotor isn't going to change anything. There is a little spring clip that goes on the distributor shaft. It fits between the shaft and the rotor. My guess is you don't have one in there. part # 8N12213

souNdguy · Jul 29, 2015

agreed on the loose rotor / spring clip issue.

as for the lack of compression... do you have the valve cover off?

if so.. look to see if you have maybee all the intakes or exhausts stuck open /down/ etc.

JMOR · Jul 29, 2015

(quoted from post at 00:13:24 07/29/15) Ok here is a weird thing. I am trying to get my tractor to start after I had to replace a piston. It won't start.

Anyway did a compression test today and it showed 0 on all 4 cylinders????? However I can feel compression when I hold my thumb over the plug hole, so there is something there. I will try again tomorrow with a new compression gauge. Anyone see this before or have any idea how an engine can show 0?!?!?!

Also- my rotor has a lot of play in it, Not the distributor, but the rotor itself. Is the rotor a common rotor used on other engines that I should be able to find at a local store?

Thanks

Tractor is 660 with gas engine

id you take apart enough to disturb the cam to crank timing gears?

tractorguy2 · Jul 29, 2015

Did you adjust the valves? The valves need to be on the compression stroke when you adjust them.

old · Jul 29, 2015

The rotor problem is covered well. As for compression as ask did you have the cam gears out?? If you did did you time time correctly?? Also spin it over with the valve cover off and make sure the valves are in fact moving and if they open and close ALL the way and have gap when they are closed between the rocker and valve

davisford · Jul 29, 2015

The distributor was never out, or adjusted.

I am adjusting the valves, or trying.

I found Tdc on cyl 1 I can see the piston and felt the compression, plus rotor is pointing towards #1 plug wire.

Now if I turn the engine with ratchet clockwise ( same direction it goes when I press starter) the #2 cylinder is showing Tdc, but the valves look wrong. Do I need to turn it a full rotation and do #2 and so on, or what is the system of turning it and adjusting??

Also timing is 1,2,4,3 but with plug wires on counter clockwise? That doesn't make sense of the rotor is turning clockwise, shouldn't the timing go clockwise????

I tried searching but am on an iPhone and had no luck

Good news is I found the little clip for the rotor

Sorry for the rookie questions

JMOR · Jul 29, 2015

(quoted from post at 17:30:36 07/29/15) The distributor was never out, or adjusted.

I am adjusting the valves, or trying.

I found Tdc on cyl 1 I can see the piston and felt the compression, plus rotor is pointing towards #1 plug wire.

Now if I turn the engine with ratchet clockwise ( same direction it goes when I press starter) the #2 cylinder is showing Tdc, but the valves look wrong. Do I need to turn it a full rotation and do #2 and so on, or what is the system of turning it and adjusting??

Also timing is 1,2,4,3 but with plug wires on counter clockwise? That doesn't make sense of the rotor is turning clockwise, shouldn't the timing go clockwise????

I tried searching but am on an iPhone and had no luck

Good news is I found the little clip for the rotor

Sorry for the rookie questions

hy are your plug wires in the cap in a CCW order? Shouldn't be.

davisford · Jul 29, 2015

Tried 3 gauges. None of them move ????

But I feel lots of pressure at cyl 1 and 4 and good at 3 , little at cyl 2 weird. It has new head gasket but I applied it dry without any sealant, thought that was normal. I did not have head machined

This time when starting it , it backfired 2 or 3 times from the carb side.

Now another strange issue. When I bought the new points cap and rotor, the cap for tighter. When I tried the new cap and rotor for first time I heard a snap and the rotor actually broke into 3 pieces. I have been trying everything with the old cap/ rotor combo. Today I tried the new cap with the old rotor and same thing. Actually snapped the rotor AGAIN !!! So cap is obvious wrong one. I will try to find another rotor local and keep trying everything

0 compression? Adjust valves?

davisford

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Bern

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Larry NCKS

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souNdguy

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JMOR

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tractorguy2

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old

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davisford

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JMOR

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davisford

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