C1: Transmittion question

[Rob M.]

Hi all,

Yesterday I took my car for a 100 mile drive (2x 50) to my office to show the car to my colleagues. Two problems appeared while driving a bit further:

1) Transmittion, 3rd gear
The shifter seems not to shift the transmittion well into the 3rd gear. It feels like it just touches the 3rd gear and I have to make sure it is fully pressed into this gear. The other 3 gears don't have this problem. Is there one rod which I should adjust (lengthen or shorten) or is my transmittion ready for a revision?

2) Heating
I must have had air in the engine because when I filled the radiator cooling liquid I fully filled it. When the engine runned very soon a lot of coolant was spilled under the hood but the engine was after a very short drive (3 miles) already on 220 degrees (end of scale). During the drive the coolant dropped so far that the heater didn't get warm anymore. I stopped at a gasstation and refilled the radiator with 2 liter (little under half a gallon) of new cooling liquid and then the heater did work again but the temperature was still very high (app. 210 degrees). I have a 180 degrees thermostate and it seem to work since the upper hose was filled with the hot coolant fluid. I'm still in doubt that there is a lot of air in the engine but I don't know how to get it out if this is the case. I must remark that I don't have the lower fan shroud installed due to poor fit of the repro part I had ordered so this could be part of the cooling problem... I'm in doubt to replace the thermostate with a 160 or 170 degrees version but I don't think this will help since the 180 seems to open just fine when the coolant was hot.

greetings and thanks for your help,
Rob.




The C1 1959 Corvette Restoration Project

[Dave Suesz]

cooling

Rob- don't go cooler on the thermostsat, it won't help. 210°F is not unusual. Check the specific gravity to be sure you have a 50/50 coolant/water mix. Put the lower shroud in. If you are not losing coolant, and the temp does not climb on warm days, you should be OK.

I'm not that familiar with your shifter, but there may be a hole for a 1/4 inch alignment pin through the shifter. If so, then you should remove the rods from the shifter, insert a pin in the hole, center the shift levers at the transmission end of the rods, and adjust each rod for perfect fit as you insert them back into the shifter. Don't for get to pull the pin out when you are done, or you'll have to crawl back under the car (voice of experience). If there is no such hole, you will have to center the lower shift levers by eye.

[Rob M.]

Re: cooling

David,

Thanks for your response. Just a question on the cooling, currently I use the green, ready to use stuff which also is used in modern cars. Isn't this suitable or should I mix it with water ?

greetings,
Rob.

[Dave Suesz]

Re: cooling

Since you added coolant on the road, unless it was the exact same ready-to-use premixed product, you need to check the specific gravity. C1 Corvettes cool pretty well, at least mine always has, my Dad took the fan off for a year when we lived in the country to see if the mileage would get better. Don't try this in town!

[James W.]

Re: cooling

Rob,

It's my suggestion that you don't mix the green coolant and the orange coolant. They have different additive packages. The green and the orange are the same ethylene glycol base, but the additives in the orange coolant may not be 100% compatible with your C1 cooling system.

Jim

[Christopher R.]

Re: C1: Transmittion question

1. The adjustment procedure for the Chevrolet-original shifter is in the ST-12. Do you have an original shifter or a replacement Hurst shifter? Is your transmission a 3 speed or a 4 speed? Yes, the adjustment procedure involves disconnecting the rods; centering the shifter; and, lengthening or shortening the rods. There is a swivel on the threaded portion of the rod that adjusts its length. The Hurst shifters had a centering slot that took a 1/4" bolt that locked the shifter in neutral. Not sure how the original shifter was locked into neutral. Adjustment can also be done by feel.

2. The temperature gauges on these cars are notoriously inaccurate. They tend to read high. You first need to determine if an indicated 220 is really that hot. Buy an infrared hand held gauge. Point it at the thermostat housing and read what that says when the gauge says 220. These gauges now go for under $100 USD in the US. Useful for other things too.

Air pockets will usually work themselves out after you run the car a few times. Keep overfilling it after it cools down. At some point it will expel the excess and settle at the right level.

Don't replace the thermostat. It won't help. Do put the shroud in. But you should be able to get away with not using the shroud if you kept your speed over 30-40 mph. The shroud is most needed at lower speeds.

When you filled the radiator at the gas station, what did you use? Straight water? Or, an antifreeze and water mix? You shouldn't mix antifreeze types. That is, keep them the same color. The system was designed for a 50/50 water and antifreeze mix. If you filled up with water at the gas station, you've diluted your coolant mix. That shouldn't hurt cooling capability much, but you won't have the freezing protection you might need.

[Verle R.]

Re: cooling

Mixing green and orange coolant (antifreeze) results in a corrosive compound that will cause siginifcant damage to aluminum parts.

NEVER mix green and orange coolant.

Verle

[Verle R.]

Re: cooling

Rob,

I don't know what antifreeze products are available in the Netherlands. Most antifreeze in the USA, both green and orange, are recommended to be mixed with water as directed on the container, percentages dependant on lowest temperatures possible in your location.

Antifreeze does not transfer heat as efficiently as water so I mix to meet the lowest temperatures expected in Oklahoma.

If you are running antifreeze without water you will probably run warmer than a water/antifreeze mixture.

Check your container for mixing directions.

Verle

[Rob M.]

Re: cooling

All,

I just have the green stuff but on the bottle it doesn't mention anything about mixing it with water, it just states 'ready to use'. I guess it doesn't need water and I don't know if it has the same gravity as water and if it mix well with it so I didn't dare to put water in it (yet).

greetings,
Rob.

[Rob M.]

Re: C1: Transmittion question

Chris,

Coolant:
Thanks for your explination, about the coolant see my remark above (no mixing with water, ready to use green stuff is inserted).

I've seen a variable resistor advertised in the CC brochure to adjust the reading of the temp. gauge, maybe I'll put also the needed temp. gun in the order so making the temp. gauge a bit more accurate is a piece of cake then.

I still wonder if the missing shroud was the cause because the engine was running a bit less hot (210) when I slowed down (e.g. standing still or running at

[Rob M.]

Re: C1: Transmittion question

Chris,

Coolant:
Thanks for your explination, about the coolant see my remark above (no mixing with water, ready to use green stuff is inserted).

I've seen a variable resistor advertised in the CC brochure to adjust the reading of the temp. gauge, maybe I'll put also the needed temp. gun in the order so making the temp. gauge a bit more accurate is a piece of cake then.

I still wonder if the missing lower shroud was the cause because the engine was running a bit less hot (210) when I slowed down (e.g. standing still or running at low speed). When driving on the high way (outside temperature, appr 18 degrees Celsius) at 60-70 mph the temperature went up to appr. 220 (end of scale). It looked more like there was so much air in the engine that the coolant level dropped so far after 40 minutes of driving that even the heating stopped due to lack of coolant.

Transmittion:
I just adjusted the 3rd and 4th gear transmittion lever and I have to take the car out for a test drive to see if it was sufficient.

thanks for the advice,
Rob.