# John Deere 670 In need of Advice/Help



## fratra (Jun 11, 2012)

I have an 1991 670 my fater-in law gave me. It has been sitting and hasn't been started for years because of his health issues.

Overall it's in pretty good shape considering and it only 330 hours on it.
The battery box is rusted out and needs replaced. the front grill is missing and needs a new seat. The biggest issue is I can't get the starter to even turn over.

Availability of parts seem to be few and expensive. If there isn't much wrong with it I will repair and keep. If it's too expensive I will probably part it out.

Any advice on trouble shooting getting it started or places for replacment parts?

Thanks.


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## sarge1572 (Jun 30, 2008)

I don't know anything about the 670, but I HAVE had some experience getting old cars running.

You say the starter won't turn the engine over. If it's been sitting for "years" it's likely the cylinders have rust in them and the pistons CAN'T move. The quickest way to see is to take the cylinder head off. If you're not in any hurry and don't want to start tearing the engine down I've had limited success pulling the spark plugs and squirting a LIBERAL amount of Marvel Mystery Oil (MMO) into each cylinder through the spark plug hole and let is sit. I just bought a 1966 Alpine that hadn't been driven since 1984. Oiled the cylinders, let it sit for a month, adding a squirt or two of MMO each week. Then I put it in 4th gear and rocked the car and viola!! The engine turned over. I rocked it slowly until the crankshaft completed one rotation. When I tore the engine down I was surprised at the condition, considering that it had been sitting nearly 30 years! I'd do the MMO, pull the spark plugs out completely (to eliminate compression) put it in high gear, high range and rock it until the engine starts to turn over. Continue until it has one or two full revolutions. With the spark plugs out, see if the starter will crank it over. Turn it over several times with the starter to pump some of the MMO out, put new spark plugs in, prime it, and give it a try. 

If it won't turn over while trying to rock it, you can try a breaker bar/socket on the crankshaft pulley nut with a cheater bar on it and try to crank turn the engine that way. If it still won't turn it's likely the pistons are seized in the cylinders.

Good luck.
Jeff


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## dsty (May 4, 2019)

fratra said:


> I have an 1991 670 my fater-in law gave me. It has been sitting and hasn't been started for years because of his health issues.
> 
> Overall it's in pretty good shape considering and it only 330 hours on it.
> The battery box is rusted out and needs replaced. the front grill is missing and needs a new seat. The biggest issue is I can't get the starter to even turn over.
> ...


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## Tx Jim (Jul 28, 2020)

Since tractor has been setting idle several yrs I would remove glow plugs from engine cylinder head & put a some oil inside the combustion chambers. After a few days attempt to rotate engine which if crankshaft rotates will expel most of the oil. Reinstall GP's & with the aid of a known good battery attempt to start engine. When attempting to start be sure trans & pto are in neutral & fuel system has been checked for any presence of air.


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