bent push rods in 1949 216 ci chev..?

[creeker1]

Hi,first time here: Sorry if this is common knowledge, but I could use some advice.
My old stock 49 chev 1 ton has always run great when I've needed it too. I only use it rarely, for hauling firewood a few times a year.I have owned it for 25 years, or more.It never miss's a beat.
I started it up the other day,and it knocked like never B4, then wouldn't start again. Long story short, I removed the valve cover, and push rod cover, and found 3 bent push rods, and 3 stuck valves. I freed up the valves with WD40,replaced the bent rods,and put it back together.It ran great for a good 1/2 hour. Very Happy.
Next day,I tried to start it again and the same thing happened, only this time it was 5 bent push rods,5 intake valves where siezed up. Very Unhappy.
The exhaust is rusted out, and I have been using unleaded gas forever.
Any Ideas..? Thanks,

 

[Kens 50 PU]

Welcome to the forum, Creeker1!

Repost this on the '47-54 forum. You'll get some real good advise!

 

[azcarman411]

Sounds to me like your gas turned to varnish. I've seen it happen before, just like glue in the guides. Chris

 

[Chiro]

Sounds to me like you have no oil to the top end of the engine. Gallery in the head might be clogged. While you had the rocker cover off, did you notice if there was oil coming out of the weep holes in the rockers when the engine was running? If you replaced the push rods and fired it up, even without oil, it would run for a while before the valves seized and then bent the push rods. These engines were designed to run with little oil to the top of the head, but not to run with no oil. So, freeing up the stuck valves by lubricating them would allow the engine to run for a while like you said and then seize up again. You should pull the little NPT plug on the push rod cover side of the engine head about midway down the length of the head. This is the oil gallery to the head. check to see if it is plugged up or full of gunk or worse...dry. If you only run the truck a couple of times a year, sediment could have worked in and just crudded up the whole works. Common fix as I understand it is to plumb an oil line from the fitting where the gauge runs into the block on the manifold side of the engine around the back of the engine and into the gallery plug hole on the head on the rocker cover side of the engine. This woud definately give you plenty of oil to the top of the engine and ensure that the valves are properly lubricated. BTW, I personally would not use WD40 to free up the stuck valves. I like Marvel Mystery Oil for that task. If you get lubrication after you plumb the new oil line, switch to a thin full synthetic oil like 5W-20 or 5W-30 for a while. Synthetic oil is very slippery and very detergent and will clean out the galleries in no time flat. How's the oil pressure at the gauge BTW? Replace the bent rods, fre up the stuck valves with Marvel Mystery Oil, pour fresh oil over the entire valve train and run it again, making sure to check the weep holes on the rockers for oil seeping out when running. If no oil comes out of the rockers within a VERY short time, you have a plugged gallery and no oil to top of engine. If this is the case, plumb the new line as mentioned, pour more fresh oil over the entire valve train, fire it up again and check the rocker weep holes for oil coming out of them when running. Just my two cents as a hobby mechanic. I am sure others (like Nate) will tell me I'm wrong, but it makes sense to me.

Just posted this and saw Chris's reply after posting. He could be right about the varnish because he is right on with the advise as usual, but check the rockers for lubrication just the same.

Andy

 

[Zig]

And his avatar is a GMC. Yes, he IS smart!

 

[vwnate1]

Hi Creeker !

WELCOME to The page ! .

When you get a moment , come on over to the '47 '53 page , that's a real Nut House and full of good guys who know your truck from end to end .

Anyway , like Andy said , use MMO or ATF on the valve stems to loosen them up , WD-40 is crap , throw it out .

Once you get the new (used) pushrods replaced and the valves adjusted and engine runing well again , drain out the old gas (makes good weed killer BTW) and re-fill the tank to the top with regular and add a whole pint bottle of MMO , that should prevent a re-occurance if sticking vlaves .

I'd run the truck and get the engine really hot then do an oil & filter change
as there may be some crud , sludge or water (acid) in there from lack of use ~ even though it may only get a few miles each year , it still needs _HOT_ oil changes and synthetic oil is the best .

Don't expect to see much if any , oil pressure @ idle and only 10 ~ 19 when going down the road .

If you've had this truck all these years it should be fine without a buncha $ tossed into it now .

See ya on the AD page !