VCCA Home Forums TECHNICAL - 1945 AND EARLIER 1933-1936 34 Pickup overheating

Yes, I have read the postings at least through 70. So much good information. And yes, I have read Peter postings on overheating. Thank you Peter, and those who helped him. I am new to this forum, having just bought a 34 Chevy pickup. This truck was "restored" 40 years ago and sat in a garage since then. Not sure yet if it is a Master or a STD. It does have a 120 inch wheelbase, but all the gauges are centered. Maybe it is a hybrid. The truck overheats quickly. Replaced the thermostat with a 165. It still overheats. The lower radiator hose is kinked, so it obviously has no wire in it. I will replace that with a wired one. Both hoses get hot. There are bubbles in the radiator, more with a run of the accelerator. There is actually a light banging sound too, which seems to be the bubbles inside the radiator. So i am going to begin by following the head torquing sequence to 75 ft lbs, but suspect I will have to replace the head gasket. I will begin researching where to get one. The block serial number is 837231. Thank you all for being out there, and I am open to additional suggestions. I believe the most important thing you can know, is what you don't know. I don't know 34 Chevy's. Maybe 47 Indians some. I will post as I go, not to educate you guys, but as a source for the next new guy to read in solving his overheating problems, which seems to be a common topic, and I might add no pun intended, a somewhat heated topic !! Have patience with us new guys, you were there once too.

All 1934 trucks had the 1934 Master pasenger car engine. The only difference is there was a restrictor in the insulator under the carburetor to limit power at higher engine speeds..........The head gasket would be the same as a Master car. I would suggest getting the gaskets from a sorce that sells Best brand gaskets.
While anything is possible it sounds as if either the head gasket is bad or the head is cracked.
If it is a 1/2 ton truck it will have a 112" wheel base. Will have 5.50X17 tires.
1 1/2 trucks were much, much longer.

Thank you for your reply Yes, the tires are 550 x 17

Any suggested vendor for the gaskets ?

YES...www.fillingstation.com...

Guy
Welcome to Chatter. I note you have already read through a pile of postings on a common problem so I guess you know there are several possible causes. There are 2 main possible causes of the bubbles in the radiator, the easy 1 to rule out is to tighten the packing on the water pump shaft, another is not so easy to fix but you have mentioned it is a blown head gasket or cracked head. The 2 latter will cause overheating as well while the 1st often does not cause overheating.
Tony

Welcome to Chat. Please pull the head and check for "sheets of rust" in the block and head. This is what these engines "do" when stored a long time. You can not just pour water/anti freeze in there and crank it up and expect it to run "O.K.". "Sheets of rust" will break up with the use of a engine cleaner/water. Then they will also break up into smaller chunks and this plugs up the openings where the gasket on the block/head is. Also plug the water pump, raidiator. Flushing backwards will only cause these rust chunks to float into a new hole. Flushing your radiator backwards may free up large chunk rust that is plunging the small holes in the tubes in the upper tank. Be sure to remove both hoses before flushing. The radiator runs with "head space" (air in the top) not like a modern system to allow expansion of water. The radiator has a sprinkler in the top that fans out the hot water. This may be plugged up. Back washing may free this part of the system up also. Water level will drain out the overflow tube until proper level is reached. Many people mistake this as not proper but in 1936 that was normal. The system is non-pressurized. Fluid is never right up to the top of the opening in your radiator. You may add water when temp. gauge starts to rise. You are right on the hose. Remove and check thermostat. Place it in a container with water, put it on the stove, apply heat, watch it open. Proving that it is working. Good luck. There is lot of good advice on this chat site.

ok. So I pulled the head today. I took pictures of the block, front to back, cylinder head gasket both sides, and the head. I don't understand how to include pictures here. If any of you knowledgable folks are interested in helping a 67 year old newbie, send me an email and I will send you the pics to help me diagnose Haddie, 34 Chev pickup.
guymonroesf@gmail.com

My plan, subject to everyones input, is to clean the surfaces, look hard for any cracks, and if seeing none, put her back together with new gaskets. Not sure yet how to torque that one headfbolt that lives under the temperature sending unit. I usually pull on a torqued one, then put that much oomph into it on the one that the torque wrench can't fit.

one piston does look very different than the rest, lots of extra weird stuff on top, I'm thinking that was the one pumping compression past the head gasket into the cooling system and the weird stuff was water mixing with the fuel.

good news is, not a ridge on the cylinders.

I bought this girl to give me something to do......and so far she is giving me plenty !!

any tips are greatly appreciated.
guy

I did tighten the packing nut. That took about a 1/3 turn, then the grease cup. That did not resolve the problem. And yes, flushing the block and radiator are on my list of to do's. You guys are great, and thanks for all your input.

take the cylinder head to an automotive machine shop and have the head checked for straightness and also cracks. They use a special system checking for cracks and can repair them if found.

Take a machinists straight edge and check top of the block, end to end and angled end to end looking for possible runout, using feeler gauges. Ask the machine shop whats acceptable.

Next take each head bolt and check the shaft for stretch visually and also end to end using a caliper. If any problems you can get new ones from the FILLING STATION.

probably the most common problem is somebody finding that cylinder # whatever is leaking due to the pure white clean spark plug , owner gets his handy dandy 18" long socket bar and over tightens the bolt causing it to stretch and create a weak spot. If the bolt no longer has the correct clamping power it creates a weak area.

There is a whole correct method to doing these repairs so you do not have to do them again.

Do it once, do it right

mike lynch

I have found if a cylinder is getting water most if not all of the black will be gone leaving that cylinder clean metal. While the head is off I would be scratching as much gunk out of the water jackets as you can, remove the lowest water fitting you can find and use that as the flushing exit point for the gunk after you have thoroughly scratched all you can.
Remove the radiator and have it rod cleaned (at least 1 tank removed and a suitable sized rod poked through all tubes so water definitely flows. This can be done while the head is being checked and serviced.
Tony

Thank You Mike and Tony. I shall follow your advice. Doing things right the first time pays off in the long run. Again, your help is appreciated.

There seems like 14 holes for water in the head. Twelve match up to holes in the block for circulation. Of those 12, 10 were occluded with rust and gunk. I think that could well be my problem. They cleaned out, as far as i could go, quite easily. Today I will take the head to get it magna fluxed to see if there are any cracks, none visible to the naked eye.

as well as the head gasket, carbon leakage between 5 &6, and water leakage at number 4, as shown by wet head bolt and gasket evidence.

While it is apart have the machine shop check the head both block and manifold surfaces for straightness. Also check the top of the block. Anything more that a couple of thousandths can spell trouble in the future, particularly the head/block.

Guy, the only other difference with the Master engine found in a truck is the cooling fan. The truck fan is slightly larger in diameter, but it is the increased blade width that moves significantly more air through the radiator. I actually found a truck fan for my 1933 Master Coupe and it improved the cooling.

With reference to posting pictures, that is a mystery I have not cracked. I posted one picture in the 1933 - 1936 Members Cars section, but a large version of the picture will not open when you click on it so you can only see a 1 x 1.25 inch picture of my 1933. I see other have the same problem, while others don't. PFM, so unless the website receives a massive update I would not plan on posting photos.

Engine blocks and heads are extremely hard to find. I think the best thing you could do is to take it to a machine shop and have them check it out. But do not trust them to clean out your block or head. Doing it yourself is not all that hard. Get all the rust and rust gunk out of the bottom of the block. A power washer is good on that... Or high pressure garden hose. I also use air pressure, too. I run a wire through every hole I can find in the head. I do not have to tell you to wear safety equipment. Oh! the garbage that comes out! If you do have a crack it can be fixed. The better machine shops can make it like new again. Trying to find these parts are very hard. Do it right the first time and you will not have to do it over. Gasket sets... there are many vendors that sell these. Look on the net. Head bolts can get stretched with age and over tightening. New head bolts are on the market. They use to use a special off set wrench to get the head off with called a "Manifold Nut Wrench". When going back use the proper tightening order. I use three rounds of proper order in tightening the bolts to the correct pressure. I start light pressure and increase each round until done. The old book says to check your head bolts and manifold bolts after 500 miles. You might be surprised at what "setting in" will loosen up. Check with a local parts place to see if they have it or can order an off set wrench. Kanter Auto Products sells a lot of parts. kanter.com But we each have our favorite suppliers.

Thank you all for the information. The head is at the local machine shop, a good old honest machinist who has worked on my old Indians, to be magna fluxes and checked for warp. Thursday or Friday I will get it back. I'll let you know what the machinist finds. He knew what the engine size was by the head and valves. He has been around the block.

Does anyone have a good picture of the water circulation holes in the engine block. My two center ones were at about 3/16 of an inch open. In the matching head they were about 1/2 inch. I have carefully chipped away, and now have drilled them out to .415
The holes do not seem to be the exact same size everywhere.
The stuff being drilled out is tough, but not cast iron tough. It is almost a grey metallic color. The inside walls of the hole is very, very irregular in depth, so I'm thinking is was not part of the original casting.
I don't think I want to drill them out more, until I know more.

the water hole opening in the block or head has no relation to the opening in the cylinder head gasket.

I believe the water openings in head gasket were used to slow the water flow down. Allowing the water/coolant to absorb more heat from the block.

For instance a 1931 Pontiac 6 head gasket was full of 1/2" water holes , but the same motor produced for 1932 had most of those same holes eliminated . Only explanation is an upgrade to the way a 1932 Pontiac 6 cooling system operates. You so rarely see the 32 , its hard to get an accurate opinion.

Oldsmobiles of the mid 20's of the 24-25-26 -27 had major changes to the cylinder head gasket design , sometimes mid year.

I'd leave to stock holes alone.

The main problem with cooling these early cars is the fans cannot draw enough air thru the radiator. 4 blades really don't cut it stock. The truck fan has a higher pitch on the blades and that seems to cure the problem, but every thing else.......radiator, block, timing all have to be right.

mike lynch

One thing I learned from experience is that the crankshaft pulley must be correct for the engine. My '34 kept boiling over on warm days until I figured out that the crank pulley was too big, forcing too much water into the top of the radiator, then overflowing before it could drain down through. Adding more water would not help. I tried adding a restricting washer in line but that didn't help at all. Only after I changed the pulley to a smaller one did I cure the problem. As someone stated above, the water level will normally be well below the top of the overflow tube.

Ron
By reducing the crank pulley (harmonic balancer) you effectively slowed the generator, water pump and fan. As a general rule the water pump is capable of shifting more water than the radiator is capable of flowing so slowing the water flow rate to match radiator flow rate which may have helped in your situation.
Tony

Results back from the machine shop. The head has no cracks. However, the head is warped by 11 thousandths. He plans to take 12 to 13 off to correct it. Hopefully I will get the head back tomorrow and put it on. I will check the dampener pulley for correct diameter as well. Thank you all for your replies.

make sure you also have the head bolts or studs checked for stretch. If they have been ++over stretched++ by over tightening , then they will not be able to apply the torque clamping evenly on the cylinder head..

Also see if the machinist has a bottoming tap for the bolt holes.

Try to borrow a clicker type torque wrench where it snaps when you have hit the correct dialed in number.

DO IT ONCE, DO IT RIGHT.

mike

Will a good machinist know how much stretch is too much ?

Any stretch is too much. Easiest way to check is to line the threaded section of two bolts together. One will have head on left other on right. If the threads of the two bolts do not fit together at least one is stretched.