VCCA Home Forums TECHNICAL - 1945 AND EARLIER 1933-1936 1935 - 207 engine block water drain.

Where would a block drain be if I have one on my 1935 - 207 engine?

From the 35/36 Repair Manual, it looks like the drain cock was added in 1936 to accommodate the draining of the full length water jackets. On the 36, the drain is on the lower left center of the block.

The 1935 and prior were drained by the lower radiator hose.

Thank you...
I installed a "Superstant 160". I will flush her again. She runs all day at low speeds. When I take her on the highway 50-55 MPH the temp runs up to about 205-210. A little gurgling when I shut down but no overheating. I read a previous post about the heavier thermostat. That and boredom prompted the clensing. A petcock would be nice. Will advise.

The fact that it heats up at higher speeds leads me to think the core is plugged-up. Does the core feel equally hot in all areas (don't reach into the fan)

Above the fan is 170-180. In front of the fan is 135-145. Laser gun from Harbor Freight. Thanks for the heads up on my fingers! I had it serviced at the local radiator shop last fall. The car that I could not drive slow (aka parades) because she overheated did an about face and now can run all day at 5 MPH. Go figure???

WISEBRI........try back flushing the system................. hi-pressure garden hose down the thermostat hole to hopefully dislodge any particles. Use something to collect the water/antifreeze and inspect it afterwards for debris. Make sure all the fins in the radiator are tight against the core tubes.

Highway speeds of 50 mph with thermostat of 180 should allow the airflow over the rad core to remove all the heat generated in the water and not run it up to 210. You might also try pressure washing the rad core from inside the engine compartment to blow out dirt, bugs , flys and other insects in the rad core.

A car I owned, a 35 chevy, had a very large olds motor in it and ran hot at 210-220. I back flushed it, changed the thermostat to a moroso 195, changed the fan to a 7 blade Chrysler with a wicked pitch. The motor had 2 temperature gauges in it...........one was in the right rear part of the cylinder head and the other was directly beside the thermostat housing.

At the thermostat the gauge would read `195.........at the back of the head where the water began its journey thru the block, was 160-165. The sysem really only removes 30--35 degrees of temperature from your coolant. Trick is to get it to run consistently in the 180--195 range all the time, once its warmed up.

mike lynch......madmike3434

Thanks Mike. I ran the hose down the thermo housing. And let it drain out of the radiator petcock. A little rust at first but ran clear. A new 160 stat. I drove it about 15-20 minutes but too much traffic to get her up to 50-55 mph. Temp was around 170-175 max. I fear another radiator is in my future. My tanks have been repaired before. I am not sure it is a candidate for a core transplant. I have been searching for another 35 std. radiator with no luck.
Joe

JOE, altho its been a while since I have been to the Dunkirk NY may swap meet, I always saw 3-5 NOS radiators for 34-35 standard at that meet. Actually I used to see them fairly regularly on ebay usa, but not in the last 6 months that I have noticed.

Why not go to ebay and do a search using " 1934 Chevrolet radiator NOS " "1935 Chevrolet radiator NOS ". Use the ***advanced*** search word right behind the regular search button on the right. If there is nothing available use the SAVE SEARCH and click on the box to send you and email if one gets listed. One might not show up for 6 months but when it does you will get an email...........has worked way to many times for me.

Keep watching your temps especially on a 80--90 hot day and watch how it performs. If your thermostat is doing its job, hoses are not collapsing and you have no obstructions in core , you should be fine.

I hear good things about those water wetter products taking 15 degrees off your top temps. I have no need for them , but others like yourself may.

mike lynch

mike lynch

Wisebri,
Running the back flush out the petcock will not create enough flow rate to effectively rinse out much trash. I would be better to remove the lower radiator hose so the volume of water passing through the block and head are as much as your hose and cooling passages can produce. That way you get flow to more of the cooling passages. Low flow severely limits the water path though the engine.

If the engine is running hot it is actually the radiator that would need back flushing also.
Remove top and bottom hoses and force water through the core in both directions (top to bottom and bottom to top). Actually wather pressure is not enoungh and water + air would be better.

OK thanks again. I will pull the top and lower hoses. Flush from the radiator top fill as well as through the lower hose both ways. (Block and Rad)

From a different angle...I would make sure the fan belt is tight. A loose fan belt will pull at slow speed and not pull at fast speed.
Have you checked your Octane Selector Knob? If it is set on "0" that is for 64 to 66 Octane Rating of Gasoline! (Buy any 66 octane gas lately?) 80 Rating of Octane Gasoline should be set at 8 degrees advance. Proper setting gives you maximum fuel economy and maximum power. A late or retarded spark will cause an engine to run hot, too. Be sure to oil your slide to the vacuum advance. It could hang up causing it to be advanced.
Just something to check out from another angle.

Thanks. I did tighten the belt a little. The octane is on +8. She runs well. A little popping through the exhaust when I use the throttle when she is cold. I will double check it all tomorrow.
Joe

Where the octane selector is set means nothing if the actual timing is unknown. First the octane selector should be set at 0. Then the timing is set with the ball on the pointer. Now the timing is set for regular grade gas in 1935. Next the octane selector can be advanced to 8 or 10 Deg.
Don't make the belt too tight. The wide belts are not adjusted as tight as the narrow belts on the later cars.

My car is almost as much work as my wife! I seem to spend most of my time in the garage though???
I will look for someone with a timing light today. Thanks again All. I drove 30 miles the "around town" temp is down to 170-175 now. Which is 5-10 degrees lower and great. When I took her up to 55 Mph she hit 185-190 but the traffic prevented further space shuttle like speeds in the 35. I did find a slow leak in the lower hose when I pulled it and re flushed. The clamp pinched it. I do have a steel elbow there. I did not like the flow rate on the radiator with the garden hose going up or down the rad. So it's back to the garage today with a timing light. We are in the right direction it seems. I am swaying toward the radiator flow as the culprit. The temp now is much more enjoyable.

I run high test. Should I?

You can run nthe lowest octane gas you can find.

Old gas was at 60 Octane. Today's is at 87 or 90 as posted on the pump in Regular with 10% Ethanol as required by Federal Law.

Does a higher octane burn cleaner and cooler?

absolute waste of your $$$$$$$$$$$$$$$$$$$, just run the 87 octane. Sunoco 94 and others like it are for high compression 11---12 to 1 comp motors, it serves no good to run it and just costing yourself MOOOOLA.

mike lynch my 2 centavos

Higher octane burns slower....so with a high compression (ratio) engine you don't get pre-ignition (pinging) under a load.
Thats the last thing you have to worry about with a 1935 Chevrolet.

Advice is much appreciated. I was unable to find a timing light today. The fuel saving should afford me my very own timing light.

I drove her on the highway yesterday. She is building pressure and blowing the coolant out of the overflow.

Your now at 212 degrees and boiling.
mike

What does the water flow look like coming out of engine with the thermostat out? Have you back flushed the engine with a garden hose?
Do you have proper air gap at the top of the radiator to allow the water to "fan out" inside? Or is it full to the top?
During the flushing did you get any rust chunks?
There are still a lot of questions here.

Thanks for asking! As she sits right now the radiator was serviced last winter. Repairs were made to the tank and it was rodded out.
I then flushed out the engine both ways. All was clear. I found the baffle behind the water pump was missing. I installed one and replaced the water pump. After all that the issue changed from low speed heating issues to higher speed cruising heating issues. Now I can drive her all day at low speeds without problems. Yesterday I took her on the parkway for 5-7 miles and she got hot so I got off and continued for another 5-7 miles on back roads. She was running about 5-10 degrees higher than before we got on the parkway. Nothing boiling over. She sat for 3 or 4 hours at the car show. We left and she did the same thing.
Today I opened the radiator petcock and green water came out which should not be as I added 3-4 gallons of fresh water yesterday while on the road that must have blown out of the over flow. There was no boiling over the top side. I assumed all the anti-freeze would be gone after adding so much water yesterday. The 160 thermostat was replaced a few times.

My next thoughts are that the rad cap is not holding pressure. I would check that before going farther.

Older gas stations had this simple tool for checking rad caps to see if they hold pressure. Maybe napa or pep boys or ?? other automotive parts tools sellers.

my radiator has had the top rad cap/ornament holder removed , hole filled and replaced with an 90 degree elbow slightly lower down on the top tank , soldered in and a 15 pound cap applied.

It hopefully might be as simple as the rad cap not holding pressure.

mike lynch.........

The pressure is constantly being released through the overflow tube....the cap doesn't hold pressure.
Possible causes of overheating.
Water pump packing sucking in air (bubbles).
Radiator core restricted. Cleaning seldom helps, a new core is the only fix.
Cracked head or bad head gasket.
Too lean of a mixture or incorrect timing could be the cause (not common)
From what I have read 1935 Standards had a "running hot" problem - fix is installing a 1934 Master core and modifying it to fit.

See "new radiator" thread below.

Thanks all. A recore is not an option as my tanks are weak. So if I tackle pulling the radiator again I should replace it. I see Wizzard, the Brass Works, Walker, and Griffin now make replacements. I won't let the car get that hot again.

I went through the same thing. After buying a new radiator, it still ran hot! Finally pulled the head. (I had flushed the block both ways several times until I did not get any rust out.) To my amazement I found rust chunks blocking the holes between block and head in the gasket area! Had I done this first I would still be running the old radiator. It is a toss up but that is my two cents worth.

Well at this point I might as well pull the head too. I have flushed it on several different occasions both ways. Never any foam in the water or water in the oil. Thanks I appreciate all the help.

While I had the head off...I took it to the head shop and had it magnofluxed for hare line cracks around the valves. Guess what? Yep, it was busted. I got a head that was good and put it on!

I have a 981 head that is already rebuilt. It need my shaft and lifter assy. from my head. I am reluctant to put a good compression head on a "not rebuilt" engine. Especially since she runs so well.
I am re-thinking doing the head at the same time as the rad. replacement so I can diagnose where the problem lies.

Update. The "direct fit" radiators are direct if are sporting a small block V8. I will take the original radiator to be check again to be sure it is the culprit. My hopes were that the over flow tube was clogged or crimped. Not the case. So if the radiator comes back good I will start digging into the engine. Again, she runs so well though.

If you are running a Non-pressure system and fill it up like a pressure type system it will over flow until it reaches proper level. The radiator must have "head space". That is an air space between the top of the radiator and coolant level. This space does two things. First allow for the expansion of coolant when it becomes hot and secondly to allow the "internal fan" to properly fan out the water as it makes the turn into the top of the radiator. This baffle spreads out the coolant over the tubes in the top tank. Proper coolant level is often misunderstood along with overflow on these models.

Although I don't have a '35, I have run into a couple of heat issues that I think are worth mentioning.

1. I used to have a 1958 panel truck that was overheating. I had the radiator cleaned and rodded, which helped but did not solve the problem. I was told that even though water flowed freely through the radiator, the old core was just not transferring as much heat as it should (the fins separated from the tubes). A new core attached to the old tanks solved the problem. So, good water flow does not necessarily mean good cooling.

2. In prepping a 1928 engine to run after sitting 40+ years, I pulled the head just to 'look things over'. I found that the previous owner had used some kind of sealant on the head gasket. Not a crime unto itself, but he put so much sealant on that the water holes between the block and head were SEVERLY restricted. Glad I pulled the head for find this error.

Hang in there and keep us posted. With all this mental exercise, you might never get dementia!

Cheers, Dean

Thanks all! I was blowing out as much as a gallon or more at each "stop to cool down" I made. I found the over flow tube to be clear. If the radiator proves to be operational, it's on to the engine. There is a great rad shop 40 minutes away who specializes in old stuff. I have a date with them.
As frustrating as it may get. All will agree it's all good.

I would suggest that if you are going through that much water that you have a look at the head gasket. On the newer engines that is almost a 100% guarantee, on the older engines less so 90% maybe.

Although not 100% sure BUT IT SOUNDS LIKE BLOCKED UP WITH RUST. If you are blowing that much water after shut down. It can not circulate right.

Or has the incorrect head gasket.

I am loosing the water as I drive. Not much after shut down. She gurgles and blows pressure when I pull over.
Went to Cap-A-Radiator today. The radiator is running at 30-40% on the flow rate. The tank is too bad to be a candidate for a core transplant. So it is onward for the Griffin Rad install, boo hoo. I have not located one 34-35 radiator anywhere.
We are going to pull the water pump for a repack and a look see inside. The "direct fit" rad sits nicely in all the brackets. I have to modify the hose connectors with aluminum elbows. Then we will tenderly check the grill shell and fan blade space for fitment.

There is an ad in the Generator and Distributor Magazine (The Vintage Chevrolet Club Of America's official magazine.) that has radiator works in there who can build you one.

Found it. Thanks

She lives! Left the engine in the car. Pulled the water pump and side freeze plugs. My mechanic used a commercial high pressure power washer. I spent hours poking and prodding everywhere I could. Power washed again. Then he scoped inside the block with his camera. We agreed the block was not near as bad as the head when we started and now even better.
We flushed and flushed, reverse flushed again and again. Water clear, we re-installed. Ran it flushed it. Re-torqued and ran it, flushed it. She has not gone over 155 degrees in stop and go as well as 4 - 5 exits at 55 mph. I expected much worse in the block and wonder why the head was so bad. End of the day, she lives and runs better than ever.
Thanks for all the help!!!

Nothing like one of those gas powered washers to shake the rust out, regular tap water pressure can vary all over the map....maybe 80 pounds pressure at tap

washers......1200 + pressure . Takes the paint off you car to if not carful !!!!!!!!!!!!!


glad you got the fix........HAPPY MOTORING ONCE AGAIN
mike

Thank you. She's on top of her game.

Good for you! That is the way to go! That is what I had to do. I keep a "rust preventative" in there with the fluid all the time. I am proud for you!

Thank you. You guys are what keeps our cars on the road. I can't believe the difference with the 981 head. It is nice to watch the road instead of my temp gauge. I spoke to an engineer at Griffin Radiator. They will modify their "direct fit" to accept our radiator hose size and direction. He said in 10 years with the company there has never been a request for this radiator with an original motor application. Go figure!