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I have a 22hp intek with about 650 hours on it. It wasn't running right. I toke it in to John Deere and they said the rods were bent. They replaced them and the new ones bent right away. They said it may be cam. I tore motor apart and cam looks fine to me. It's not bent and nothing looks damaged. When I move the things the rod connects to(rocker, valve) they don't give more resistance than I think there should be. I did clean the carb out a few months before this. One of the plugs looks dirtier than the other. I really don't know what I'm doing if that's not obvious any help would be appreciated.

Take both rocker covers off and measure the length of the fully compresses valve springs.
Chances are the ones that keep bending the pushrods will be shorter than the ones that don't when fully compressed.
You can double check by trying to slip a 0.002" feeler between the coils of the springs when full compressed.
If you can not the spring is effectlvely coil bound and will cause the pushrod to bend.
This happens because valve guide slips down inside the head.
And that happens because the head gets too hot.

Well that is a little different experience than I have had. I have only heard of one valve guide slipping down into the combustion chamber. All I have experienced the guides slipped up into the rocker arm chamber. The guide should not extend more than 1/8" above the head casting in the rocker arm chamber. As said, a cooling problem usually causes valve guides to move but some say ethanol fuel is causing valves to stick resulting in guides moving. I have a fix if that has happened. Also, I can send you a Service Manual IF you like. Address below, put in proper format and remind me engine model number and what you want.

Walt Conner
wconner5 at frontier dot com

I have heard that the Intek rods are weak. But maybe smart engineering - just strong enough for 3000 rpm? Anyway, you pros should weigh in on valve interference with a rising piston. How could that happen on a pushrod motor? Hmm wrong assembly causes wrong valve phasing? Not sure if a pushrod could resist enough to bend a rod. When I first read this thread I thought maybe jest? What about hydraulic lock- gas fills cylinders?

No valve doe not hit the piston, the spring fully compresses so the spring is coil bound but the pushrod is still trying to compress it.
So the pushrod bends
One of the reasons for using alloy rods is to remove as much of the inertia in the pushrod which pushes the rocker harder after the cam has already gone past peak lift.

motoman said:

I have heard that the Intek rods are weak. But maybe smart engineering - just strong enough for 3000 rpm? Anyway, you pros should weigh in on valve interference with a rising piston. How could that happen on a pushrod motor? Hmm wrong assembly causes wrong valve phasing? Not sure if a pushrod could resist enough to bend a rod. When I first read this thread I thought maybe jest? What about hydraulic lock- gas fills cylinders?

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I think you are mis-reading the post. All references are to *Push Rod* not connecting rod. Also, as said above, there is a reason the push rods bend and if they didn't then much more serious damage would result.

Walt Conner

yes, I did misread it. thanks

Tinkerer200 said:

Well that is a little different experience than I have had. I have only heard of one valve guide slipping down into the combustion chamber. All I have experienced the guides slipped up into the rocker arm chamber. The guide should not extend more than 1/8" above the head casting in the rocker arm chamber. As said, a cooling problem usually causes valve guides to move but some say ethanol fuel is causing valves to stick resulting in guides moving. I have a fix if that has happened. Also, I can send you a Service Manual IF you like. Address below, put in proper format and remind me engine model number and what you want.

Walt Conner
wconner5 at frontier dot com

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It looks like what I am guessing are the valve guides have both pushed up on one side. I sent you an email for a service manual. Can you send me the fix? Thanks!

The fix is a new head.

BlazNT said:

The fix is a new head.

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Well that's fine for you, for others they can fix it for less than $10 and dozens have over the last several years using my method. Let us know how things work out Jim.

Walt Conner

Jim68 said:

I have a 22hp intek with about 650 hours on it. It wasn't running right. I toke it in to John Deere and they said the rods were bent. They replaced them and the new ones bent right away. They said it may be cam. I tore motor apart and cam looks fine to me. It's not bent and nothing looks damaged. When I move the things the rod connects to(rocker, valve) they don't give more resistance than I think there should be. I did clean the carb out a few months before this. One of the plugs looks dirtier than the other. I really don't know what I'm doing if that's not obvious any help would be appreciated.

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If the valves were not adjusted right when the new push rods were installed....maybe they got loose...slipped position and were bent.

You assume the installer knew what he was doing...
Both rods bent seems odd.

Measure the valve spring closed & Open height ( top of spring to head floor ) on the side that does not bend rods and on the bad side.
If the bad side is signifinantly shorter > 1/10" then ask Walt how to fix it.
Take the head off.
If the cam is the problem the valves would be touching the top of the piston & leaving a mark.
You can check this by putting a thin layer of plasticine , silly putty or similar on the piston, reassembling the head & running the starter for a few seconds.
Remove the head and look for holes where the valves has kissed the piston.
While the head is off gently push down on the piston while rotating the engine by hand.
If you feel a click then the big end / conrod is toast and may allow the piston to come up a bit higher and perhaps hit the valves.
Finally, the inlet rod should be alloy and thus bend easily but the exhaust should be steel and it is rare for them to bend.
Jump off yes but bend no.
Getting right into the obscure on the top of each valve stem is a little cup that the rocker sits on check the ones on the good side are the same as the ones on the bad side.
Lash caps do come in different heights, the mechanic could have lost yours and fitted replacement that were too long.

What is the method to reset a pushed valve guide and have it last?

Tinkerer200 said:

Well that's fine for you, for others they can fix it for less than $10 and dozens have over the last several years using my method. Let us know how things work out Jim.

Walt Conner

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I haven't fixed the valve guides yet. After reading the steps a few times it seems like an easy fix.
Where do you recommend getting parts from? I plan to get a gasket set since I need one for the bottom, valve covers and I assume the head.
Thanks

I really can not tell you that as I got my parts from a couple of whole sale houses and now thru a friend who gets them from a B&S Distributor. That sump gasket kit is going to cost you about $25 by its'self and certainly you need head gasket as that is a primary failure point.

Walt Conner

Here are pictures of the piston and the head. Seeing as I've never done this does the piston look ok? The inside of the cylinder looks fine to me.
And the head is a little discolored,I'm assuming from heat, is it ok. It also show how the bushing is pushed out.

Jim68 said:

View attachment 30131View attachment 30132

Here are pictures of the piston and the head. Seeing as I've never done this does the piston look ok? The inside of the cylinder looks fine to me.
And the head is a little discolored,I'm assuming from heat, is it ok. It also show how the bushing is pushed out.

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I don't see anything wrong but why did you take the rocker arms & studs out? I would use lock tight on those studs when putting them back.

Walt Conner

The cylinder is fine, replace the head though, because getting that guide back in place and making it stay is about impossible.

ILENGINE said:

The cylinder is fine, replace the head though, because getting that guide back in place and making it stay is about impossible.

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That is absolutely not true and there are several dozen people from the 6 forums I am active on who have done it successfully. I am surprised that a person of your experience would say such a thing. Actually there is more than one procedure which has been successful.

Walt Conner

Tinkerer200 said:

I don't see anything wrong but why did you take the rocker arms & studs out? I would use lock tight on those studs when putting them back.

Walt Conner

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I thought I needed to to get the springs out.