VCCA Home Forums TECHNICAL - 1945 AND EARLIER 1933-1936 Another bent push rod

Well, it happened again. Dang it!! I was trying to start the '36 so that I could move it to the other bay and install new brakes lines on it.

But after some failed attempts, we noticed that the side cover was "flexing" while I was turning the engine over. Dag nab it. Another bent push rod.

I took the valve cover off and saw that the second valve was stuck again and it took a rap of the hammer to get it go move down... Now I need to remove the side cover AGAIN in order to fix/replace the push rod.

QUESTION:
This engine has the rubber "umbrellas" installed on each valve. I suspect that this prevents the oil from reaching the valve guides. Possibly it stops the engine from burning some oil too.... but I'm guessing that it's probably not really necessary with a low mileage (21k) engine.

So -- if this is causing the valves to freeze up, thereby bending the push-rods, SHOULD I REMOVE ALL OF THE RUBBER COVERS off the valves? Or maybe just off the intakes?

Thanks for your thoughts.

--- Bill B
(Suffering in Seattle)

One way or the other you need to get some MMO or equivalent on the valve stems.Put oil on all the stems and give them the hammer treatment to be sure they are all moving. Turn over by hand several times while checking the valve movement. Easiest with the plugs out and a good time to give a squirt to the pistons. Let it sit overnite and turn again by hand the next day to be on the safe side before cranking with the starter.

When you do get it operating again, use WD-40, MMO, Thread cutting oil, ect and apply a liberal amount to the junction of the valve stem and the guide. You can also fog it down from running to stopping with transmission fluid, MMO, bulk WD-40, or ect.

When you know you have an engine that is prone to stick a valve, remove the valve cover before starting and tap the end of each rocker arm with a hammer and insure it is not frozen.

Dump some 2 cycle egine oil in the gas tank also.

A few ounces of MMO in the fuel tank can be a good thing.

As a teen, ('53 to '55) I did this frequently in a '41 and a '47. I had forgotten this. I think I'll begin to do so in this '41.

So, when I last ran the engine, I did add some MMO to the gas tank... but I only ran the engine for about 20 minutes. (Note: This was only the third time that it was started since the original fix.)

Since no one took a postion on it I think that I'm going to remove all of the rubber boots. Let it smoke.

Hopefully that will allow oil to reach the valve guides.

Bill
When you remove the valve springs would be a good time to check that the valves are free in the guides.
Tony

I use a product called "Engine-Stor" when I put a car up for the winter or when car will not be started for an extended period of time. Pull all the spark plugs out, and spray the cylinders while turning the engine over for 10 seconds. After all cylinders are done, spray each cylinder again for 5 seconds without turning the engine over. Put the plugs back in and put the "Battery Tender" on the battery. My cars will start right up with no problems....JIM

Here's the first photos of this NEW problem. As it turns out, there were THREE bent push rods this time!!! Cylinders 1 and 6. Arghhhhhh....





Thanks for the responses and suggestions. What you need to realize is that this isn't just a normal situation. This car has not been run for approximately 11 years. I've only started it three times and ran it for a total of about 20 minutes. And... the gas tank drain plug is stripped - and I can't remove it. So I siphoned as much of the gas as I could and then added about 5 gallons of new gas. Added some MMO to it.

It seemed to run very smoothly and the gas pump mesh is clean.
When I tried to start it last week, it wouldn't start.

HERE'S THE DEAL. If you look at the photos above, all three bent push rods are INTAKE valves. Another anomaly is that this engine has rubber boots on all intake valves. I don't believe that that this is original for this year. I can see that maybe someone thought that the boots would prevent the engine from smoking.

With about two hours of effort, Dick Olson and I got ALL INTAKE valves to turn using my drill. Some of them were VERY TIGHT and needed 10 minutes with vice scripts and lots of lacquer thinner before I could put the drill on them. But now they are all free.

My plan tomorrow is to reassemble, spray everything with motor oil, penetrating oil and Jack Daniels. Then I'm going to PUSH it into the next bay and put it on the lift. That dang gas tank is coming out - one way or another. And it WILL be clean when I finally try to start the car the NEXT time.

Ethanol blended gas can gum up valves. If you use it, plan to use it all up in a few months. It also is a corrosive and will loosen up old varnish and crud in the tank.

Bill,
I think you are looking in the right place. My son and I started a Corvair Greenbrier after many years of rest. He continued to bend pushrods until the tank was cleaned and replaced.

Mike

In 1936 there were no boots or seals used on any of the valves. 1941 was the first year to have a device to prevent excessive oil from running down the guides. It was a metal cap that sat on top of the valve spring retainer, just under the rocker arm. The 1941 used it on the intakes only because they thought the intake would suck oil down the guide. From 1942-1947 they used the device on both the intakes and wxhausts. From 1948 and up they used an O ring type seal between the top cap and the valve stem.
Excessive oil running down the guides would cause a carbon build-up on the valve stem (lower end) and cause the valves to stick.
Your problem is caused by the old gas making a varnish is this area. It is very difficult to remove with out actually removing the valve and cleaning the area with a wire wheel on a bench grinder. Sounds as if you did a good job without removing the head.
Need any more push rods?

For Sale -- 6 rubber boots for intake valves!!


Thanks Gene, Mike and J Franklin.
I made an error in my earlier posting. The three bent intake push rods were for cylinders 1, 2 and 6.

If you're interested - here's some more stuff that I'm trying to decide.

1) I will leave the rubber boots OFF.
2) I will NOT put gas back into it, until I remove the tank and purge the entire gas lines.
3) I'm thinking of leaving the push rod retainers OFF. This would allow me to replace push rods in the future without removing the side cover.

QUESTION: Should I leave the 2 push rod retainer bars in place? And should I leave the lower springs there even though I'm removing the lower rod retainers?

Gene - yes, I could use 3 now... My plan is to straighten them tomorrow and reinstall them. But if I leave the retainers off, then I should be able to swap them out easily.

I probably won't have the gas tank out and back in until late next week.

--Bill Barker

Push rod retainers....and springs on top of the lifters.
They were used from 1934-1937 and the springs assisted the regular valve springs. Weaker valve springs were used. When the helper springs are removed it is necessary to use the stronger valve springs used from 1938 and up on a 216 engine. You may or may not now have the stronger springs. It depends what the last person that ground the valves used. If the engine has the weaker sprins the valves will "float" easily causing the exhaust valves to burn. If the regular valve springs are still out I would recommend getting a set of the later 216 springs and eleminating the helpers. I did this on my 1934 years ago and it makes things so much more simple. The stronger springs will also help reduce the valves from sticking

The push rod retainers were gone in my 37 when I got it 45 years ago and I left it that way. No problems so far.

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Bill , I am surprised that nobody has said DO NOT PUT STRAIGHTENED PUSHRODS back into your engine, thats a BIG NO NO NO .!!!!!!
Once bent that area now becomes the weak spot in the pushrod and will easily bend there again. Replace the push rods with new ones . Anything else is foolishness.

mike lynch

I beg to differ...I don't think there's any thing wrong with using "straightened" push-rods...

In fact...The spot where it was bent and now re-straightened is actually stronger...! By means of "plastic deformation". Its the metallurgical term for "work hardening"...

Mike, usually I am in "lock step" with you, however I can't go down the road with you on this one. A pushrod will never bend if everything is correct. If the problem is not fixed or returns, you have just bent another pushrod. I agree that a new rod is nice, but not cost effective.

Question, how much are NEW OLD STOCK or NORS pushrods for this motor ???

mike lynch

I would never suggest straightening a hollow push rod but a slightly bent solid should be no problem.

I run tubular (hollow) push rods in my '39. The are lighter and stronger and cut down on valve noise. They were a must for modified 216 engines years ago.

I was looking at Bill's photo's of some of those wildly bent push-rods and couldn't help but think...Couldn't you use those as wind-chimes...?

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I see ONE slightly bent and 2 very heavily bent. I think that LARGE deformation in the 2 rods makes them unusable.

This metal is now stretched.
mike lynch

I tend to imagine that common sense would steer you away from trying to straighten a hollow push-rod, it just doesn't lend itself to the mechanical or physical properties that allow it to be repaired...

As far as those two push-rods being too stretched to be of any use, is debatable...We're not concerned with tensile strength in this case...Only straightness and it's length within tolerance...

Then of course there is it's re-purposed usefulness as a wind-chime...

Ha ha... a wind chime. And my wife's birthday is this Saturday, the 5th. What a great surprise... You just helped me solve TWO problems!!


I think that I'm going to post some more pictures later tonight. And, I'll give you my decision.

A friend who had parted out a '31 sedan 20 years ago, called me recently and told me he had found a box of miscellaneous spare '31 parts I could have free which I gladly took. In the box were 12 nice straight pushrods which I figured I would never need, but kept anyway. In view of your trouble Bill I guess I better hold onto them. If you get stuck, I'd be happy to "pay forward" and ship you 4. Would just have to confirm they are proper length etc. If you want some, send me a PM.