40C questions

[BradE]

l'm replacing my 40C with a different one I found just a few miles away.

At first, I thought it was a 420 as it had the 420 decal on the side of the radiator. But the SN plate clearly says it's a 40C. So the seller's brother (original owner) wanted to think he had traded up!

It has heavy duty snow cleats. About 4 links were taken out each side as the tracks now on it came from a 5 roll. The tracks are new. The sprockets are almost new, and the rolls all look good. It's been cared for well.

I was given a couple of boxes and a plastic pail of parts, some used and some new. There's a set of steering clutch fiber and steel plates, an older clutch plate and pressure plate, and two hydraulic cylinders as spares.

What I want to know is the number of hours I can expect this to have. The clock tells me 1,300 if I read it right. What would be a lot of hours for this machine?

How do I go about rebuilding the spare hydraulic pump? Is it worth it to do that and then sell the pump? should I just keep it?

One spare cylinder has a long crack down the side. Can this be welded?

It's had a new generator and regulator, with an 8 volt battery. It's not showing much charge….is there a set amount for charging I should know about? Then I can get a buddy to check the charging.

Thanks!

This was one of 124 made the week of July 11, 1955.

[Lavoy]

1300 hours is low hours, but the hour meters are seldom right. If truly 1300 hours, then it would still have the original undercarriage I would think.
No reason to rebuild the hyd pump until you need it, unless you think yours is bad.
Throw away the 8 volt battery and put in a good 6 volt, lot less problems long term. Without adjustment to the regulator, you really only have a 6 volt battery anyhow, plus probably less CCA than a good 6 volt.
Throw the cylinder away, not worth the risk of someone getting hurt or a hot oil bath.
Lavoy

[1010c]

I just wondered what troubles you have had with the 8 volt batteries i have been told they are good i have two i havent had any troubles.

[Lavoy]

8 volt battery on a 6 volt system is really no gain unless you change the voltage at the regulator as the system will only charge to 6 volts, so you still only have a 6 volt battery as the 8 volt battery will only be charged to 75% or so of voltage. Also, I have never found an 8 volt battery that has any more than about 60% of the CCA of the 6 volt batteries I normally use, so your total available watts of power is still more with a 6 volt battery.
As a general rule, increasing voltage of the battery is a Band-Aid fix of an underlying problem that will need to be fixed sooner or later anyway. I have always felt it is simpler to just fix the problem so they start well on 6 volts. Or, in situations where it is that big of a concern, convert the crawler to 12 volts and install an alternator and rewire the crawler accordingly.
Lavoy

[BradE]

8 volt battery on a 6 volt system is really no gain…. I have never found an 8 volt battery that has any more than about 60% of the CCA of the 6 volt batteries I normally use, so your total available watts of power is still more with a 6 volt battery.

What brand/model 6 Volt battery do you use?

As a general rule, increasing voltage of the battery is a Band-Aid fix of an underlying problem that will need to be fixed sooner or later anyway.

Such as issues with ignition or carburation?

[Lavoy]

I use only the Deere 6 volt, other than the Optima, they are the highest CCA I have found. They are also the longest lasting 6 volts I have found.
No, I mean electrical system, primarily starter, but cable size is often an issue too.
Lavoy

[1010c]

Okay thanks

[Stan Disbrow]

Hi,

Usually the switch to 8v is to put off having the starter rebuilt. There is little margin for weakness in a 6v starter. Which reminds me I really need to get the one on my 420 rebuilt once again.

It is difficult to get battery cables large enough these days. I make up my own, but if one buys wire too small the extra 2 volts can help. If it starts right away, that is. There isn't as much cranking time in an 8v as there is in a 6v.

The generators will rise up slowly to 9 volts with an 8 volt battery, but it takes a few hours to get there. The high charge rate drops off pretty early on a 8v battery, leaving a low rate to take a long time to finish the job. And, if you don't use the machine long enough, you will effectively have a 6v battery next time you go to start it. One without nearly enough amps....

I had a 430w wheel tractor someone converted to 12v, except for the starter. When I put the 6v stuff back, the starter had been hurt by the 12v. So, it would not turn over fast enough on 6v. So, I stuck in an 8v battery for a while. I was sorting out some other issues and wanted to put off the rebuild of the 6v starter. It did work, but in the end I did fix the starter.


Stan

[shinnery]

My experience with a 8 volt battery was about 60 years ago with a tired worn out Dodge car. I would be suprized if it had 100psi compression. Yes it started the car due to the increased spin rate but with the setting the voltage regulator had to have to recharge the battery it gobbled 6 volt headlights. there was one manufacturer that built headlights that were marked 6-8v. They would last a week or two, if you could find them in the junkyard. I know I loosened the screws on a lot of headlites to find the ones marked 6-8v. Poor broke kid spent hours scouring the junkyards for 50 cent bulbs. Never again.
Pouring a little oil down the carb. also helped to start it.
Bryce

[hydrogeo]

I agree with keeping the 6 volt and just making sure everything is in tune and up to snuff. My 40c it is by far the best starting motor in my fleet. I just found that I absolutely need to close the gas petcock if I am going to let the machine sit for more than a day, otherwise it seems to flood out.