The Stovebolt Site Forums The Shop Area Engine Shop 1954 235 engine compression

I checked the compression today on our 54 truck,after our very first attempt to start it since we got the truck.Of course it didnt start.The compression was about 40psi in each cylinder.My question is .Is 40psi enough compression to get the truck running?Im trying to figure out if we did somthing else wrong.We have spark and gas to the carb.Set it TDC.Should it run with 40 psi?
thank you john

No i dont think it will. A good # would be 120-130 psi

Dam i thought it would be enough to get it started.Even if it ran bad.

Re-check your valve adjustment. If the compression is the same, or close in all the cylinders, it sounds like you're dealing with some too-tight valves, either sticky, or just adjusted a little too tight. A couple of ounces of oil in the cylinders should raise the compression temporarily if the rings are the problem. There will be little or no increase on a wet check if the valves are causing the problem.
Jerry

thank you folks,I will check the valves again tomorrow.Then ill put some oil in the cylinders and re-check the compression again.I will update you folks tomorrow.We are just a little depressed tonight.We were hoping to hear her run today.But tomorrow is another day.

It may be easier to tow start.

This baby has been sitting for 35 years.

Have you pulled the valve cover and checked the operation of the valves? Stovebolts have a nasty habit of sticking valves in the guides and bending pushrods. If old, stale gasoline from the fuel tank ends up in the engine, gummed-up valve guides can happen after a very short time even if they were clean on startup. Always use clean, fresh gas from an auxiliary tank to ressurect a vehicle that's been parked for a long time.
Jerry

hotrod,it has a brand new tank with fresh gas,we changed the valve guide seals,took apart the rocker assemblys and cleaned them all up.we also adjusted the valves with a feeler gauge.But we are going to re-check them again to make sure.

John,

What technique did you use to adjust the valves?

How did you find #1 TDC?

If all the cyl are that low and its been sitting that long its a good possibilty the rings are stuck. Somthing you may try is ( if your comp guage has a quick connect you can hook to your air compressor), put air in the cyl and listen to where the air is coming from. If you blow alot of air out the crankcase vent i would say rings.

I say forget about the compression, make sure the valves are adjusted correctly and let her rip. If the rings are stuck, they will loosen up after it starts.

You should pump oil pressure up before starting an engine that has been sitting that long and squirt oil in the cylinders through the plug holes.

We played with the truck again today.We put some oil in the cylinders and it brought the preassure up to about 75 psi.We then did a leak down test and the air is coming out of the breather.Which i belive means the rings are bad.It is making no attempt at all to start not even a sputter,even with a little ether sprayed in there.The way we found tdc was we watched intake valve open then close on #1 cylinder,then we lined up the bb on the flywheel to the pointer.With rotor facing #1 plug.When we crank the engine we are getting spark at the plug.It is making no attempt at all.Do you folks think it should even make a slight attempt to start with 40psi of commpression?>Sorry i keep repeating myself .Was the way i stated ,that we found tdc the correct method or could we be 180 off?It just cranks like the key is off.

thank you again john

I have a 235 w/3 speed trans out of a 59 Apache. Interested??

Tom im not interested at the moment.I would like to try to get the original running right now if we can.

I would not use anymore ether. The points should be set to spec to get the best spark. In a case like this, I like to power the coil from a separate source like a battery charger. That way you get the maximum spark. I would assume that gas is getting through and you can make it squirt with the throttle? Also, you need full choke on to make it start. You could roate the timing a small amount in either direction.

The correct position for firing on # 1 can be found by observing the rockers on #1 when the pointer is at the ball. Both exhaust and intake should some play in them that you can feel. Also the rotor should be aimed at #1. I would also check the firing order carefully, which is 153624.

Isn't the ball on the flywheel 5 degrees advanced? The small triangle which comes just before the ball is TDC?

I agree with you, I just didn't want to confuse the issue. Many say static time to the ball but I would static time to the triangle which is labled UDC.

I like to watch the valves on #6 cylinder. Turn the engine (clockwise from the front) until you see the #6 exhaust valve open, then begin to close. When the #6 intake valve starts to open, the BB should be just about lined up with the pointer. The distributor rotor should be pointing toward the #1 plug position at this time. It's easy to get confused when watching the #1 valves, since the engine must be turned a considerable distance after the intake valve stops moving.

Is the electrical system still 6 volt? If so, try spinning the starter over with a 12 volt battery to get the cranking speed up. If you don't abuse it with long cranking times, you can do a fair amount of cranking with 12 volts with no damage to a 6 volt system. It will also maximize your spark.
Jerry

Truckernix, We are getting a shot of fuel in the carb.We set the points at 19.There is play on the #1 rockers ,the bb is lined up with the pointer and the rotor is facing #1.im starting to get very discouraged.But what can you do.Take it one day at a time.

thanks john

Hotrod,yes it is a 6 volt system,with a new battery.its not cranking all that fast.Tomorrow i will try a 12 volt battery to see if that speeds things up a bit.

thank you once again for your help

Folks ,sorry im a little confused.Is the bb tdc or the triangle?

The triangle is top dead centre, referred to in the manual as upper dead centre and labeled on the flywheel as UDC. The bb is at 5 deg advance. If you rotate the flywheel past the bb, five deg. which is a little over an inch, you will see the triangle. For best results I would advise you to static time it to the triangle.

http://chevy.oldcarmanualproject.com/shop/1954truck/54ctsm1245.html

1954 235
235 engine: timing mark (ball in the flywheel): 2 degrees ATDC (After TDC)
261 engine: timing mark (ball in the flywheel): 5 degrees BTDC (Before TDC)

Sorry guys, the triangle is not TDC/UC, it is used only for checking cam timing. #3 Paragraph There is a line on most flywheels between the U and the C which is TDC/UC, The ball can very from TDC/UC to 5 degrees, with 3 and 5 being the most common, depending on the engine and year.

I really appreciate everyones help.Just to fill you folks in i didnt get a chance to try anything today.Just got home from work at 8pm.I will keep everyone informed.See what tomorrow brings.

thanks again john

Hello folks,we are back with a update.We tried to get her started again today.Once again no luck,it wouldnt start.Just to update we tried the following things.We checked the compression again its about 45psi per cylinder.When we add oil to the cylinder it brings it up to about 100psi.We checked that the valves were adjusted properly.We tried static timing it in all the various timing marks described in this post.We tried it on the triangle ,bb and between the u and c .All of which we had them lined up with #1 plug.We did the leak down test and the air sound is coming out the breather tube.It makes zero attempt to start not even a sputter.It doesnt seem as though we are getting gas to the cylinders.WE have done alot of cranking and there is no oder of gas on the plugs when we pull them out.Could the low compression be the cause of no gas being drawn to the cylinders?We have not yet tried cranking it with a 12 volt battery or trying to pull start it.We have tried putting putting a 6 volt charger to the coil for spark.We are still getting spark and the carb is giving a nice shot of gas.Im still wondering though is it possible for her to start with such low compression?If you folks beleive the cause is sticking rings is there a product that i could put in the cyliders that jus might free them up?When i turn the motor to line up the timing marks with all of the plugs in the motor,i can turn it with one hand with very little resistance.Once again we would appreciate any help or guideance.

thanks john

You probably tried this:

Pour a little gas down the carb, then try to start. You might also give each cylinder a squirt of Mystery Oil, as it'll help bridge the gaps in the rings, and its nice and burnable too. I've always found pouring gas down the carb helpful to get a difficult engine to start. It gives you a starting point too. You should get a sputter, which is quite uplifting, I can tell you.

If you stick your hand over the carb when you crank it, it should still suck, even with leaky rings.

I have had engines where everything checked out and still would not start. I those cases a new set of spark plugs did the trick.
100 PSI should be enough to start it.

Chris,your right.I did try pouring some gas down the carb.Still no luck.We didnt try putting marvel mystery oil.We will give that a try tomorrow.Dave the plugs,points ,cap and rotor are all new.i didnt find a line on the flywheel between u and c so i put it in the middle to static time.what i saw on the flywheel was a #2 then the bb l u c,then when turned a little more we see the triangle.Dave you advised static timing between the u and c is that correct.Im only getting 100psi when i add oil to the cylinders.Dry is around 45 psi.Im sorry i keep repeating myself,but once again we are getting a little dicouraged.

thank you again john

Did you close the choke while you were trying? Also, when doing the static timing, the points should just begin to open on whatever mark you are using. Once you try it and there is no response, try rotating the timing one way and then the other.

John, the description about UC was just for clarification, you should set the static timing at the ball although it should run if it is even close.

I still think coast starting may be the answer.

Truckernik,I had the choke closed and i also tried advancing and retarding the timing while we were cranking over the motor.Today we are going to try static timing to the triangle.Then put a little marvel mystery oil in the cylinders.Then try to crank her over with a 12 volt battery for a short time.If that doesnt work.We will then try to coast start.Im keeping my fingers crossed.We will update you folks later.You folks are so great.Thank you once again for alllll your help and guidence.

You are worrying too much about timming. If its anywhere close it will run. Even if its off a bunch it ought to backfire. Dont count the plugs out they may be drowned with oil or fuel. If you have a good blue spark at the plugs I would try another set. Then hook a chain on her and teach it to lead.

whahoooooooo lol lol shes running,We had the timing correct everything was set correct.We put some marvel mystery oil in the cylinders.Then tried cranking it with a 12 volt battery,we had no sucess with that.So we went on to the next step you folks suggested and that was coast/pull starting.Bam the first pop of the clutch and she fired right up.We are so happy to here her running.We are still laughing are asses off.The smoke was everywhere.What a pisser.Well just wanted to let you folks know where we are at.Its back outside now to play with the truck a little more.Fill you folks in later.Thanks again for all your help and support.

Great News!

Congratulations.

Congrats! Now always park on a hill, no worries!

Thank you folks.Now for the update and our next hurdle.We had it running for about 45 minutes.It didnt stop smoking the more we raced the motor the more it smoked.We did another compression check its up to 75psi from 45psi.Thats still very low.Do you folks think its time for a ring job or do you think they might loosen up?This is the first time this truck has run in 35 years.