720 diesel cam

same tractor i asked governor question on a week ago, when i pulled the governor shaft out to check the weights i noticed the idler gear that drives the governor and cam shaft was loose. i have governor housing, flywheel, timing cover, cam gear, and cam idler off now and since i'm this close to the cam i'm wondering if there is a way to determine the condition of the cam with out pulling it and measuring it or sending it away? can a guy measure how far it pushes the rocker arms? or something like that to determine its condition? as it sits right now i can see a little pitting on the roller for the # 2 injection pump push rod, but what little i can see of the cam i don't see any pitting

i know the engine has been overhauled at some point because the head and block have the discolored paint that you get from hot tanking them, however i have no idea what all they did or didn't do while they were in there. the tractor seems to run good and dynos at 65hp.

also the loose idler gear turned out to be they put a thin washer behind the bearing which held it out enough that the snap ring couldn't go in the groove and worked its self out letting the gear move around quite a bit. the bearing looks good but it is somewhat loose on the shaft and the gear, im thinking about cleaning the oil off the mating surfaces and putting permatex 620 bearing mount on them when i go back together with it. does that sound like it would work? or should i be looking for a new gear and stub shaft?

also both weights were in tact and where they were suppose to be and everything seems free, i think im going to see if i can go over all the pivot points in the governor and tighten them up, i suppose by welding and polishing back down to size on the shafts so they are snug in the holes but still have free movement. does that sound like a good route to go with it?

sorry for long post just want to get it right the first time around so i don't have to tare into it again.
 

Factory service manual spends some time on the idler topic. Two holes are drilled and tapped down from the top of the block down into the idler shaft bore. Then the bolts are tightened down onto the idler stub and held with jam nuts.
A fresh grind on the cam and followers will make her run even better. No harm in asking the shop to ask for more HP with a mild puller cam.
 
My cam idler gear was the same way. Like Buick&Deere said, there was a service bulletin on it, which i found a copy of on eBay. It goes over the whole procedure to upgrade to a 730 style set up. I can't remember the difference now, but I remember it was a much better way of mounting the gear. I got a good used 730 cam idler gear from a boneyard, and someone is reproducing an oversized stub shaft that the SB specs. The SB tells you where to drill a few holes, which lets oil flow into the new stub shaft, and you ream out the existing mounting hole to accept the new stub shaft. I was lucky and found that someone previously had drilled the oil holes AND even reamed out the mounting hole. All I had to do was drill and tap one spot and drive in the new stub shaft. It's a little bit of a pain but now it's done right. If you want to go this route send me an email and I'll try to find that service bulletin.
 
from what i can tell the shaft itself is tight in the case just the snap ring wasn't in place that hols the bearing on the shaft which let it move side to side at least a 1/4". but if the upgrade is available reasonably i would definitely think about it so i don't have an issue down the road. do you remember where you got the shaft?

where is a good place to send the cam? Berry's in Lester Prairie MN? i have read some mixed reviews on them but they were older reviews maybe they got better.
 
(quoted from post at 13:02:00 05/29/16) from what i can tell the shaft itself is tight in the case just the snap ring wasn't in place that hols the bearing on the shaft which let it move side to side at least a 1/4". but if the upgrade is available reasonably i would definitely think about it so i don't have an issue down the road. do you remember where you got the shaft?

where is a good place to send the cam? Berry's in Lester Prairie MN? i have read some mixed reviews on them but they were older reviews maybe they got better.

Pulling board on this site are up to date on the latest and greatest.
 
On my tractor, the shaft was tight in the housing too, but the bearing in the gear had slop on the shaft. Upon checking, it looked as if the shaft was wore where the bearing rode. I was concerned that if I put a new bearing on the wore shaft it would still have some slop. I found that remanufactured shaft online and went ahead and upgraded everything to the 730 parts.

I sent you an email. I believe I found the new shaft on ebay. A 730 cam idler gear set from a boneyard, and a few miscellaneous peices from Deere.

Renaissance tractor does cams I believe. He seems very knowledgeable on these 2 cylinder diesels. You can Google them and find the number.

The cam in my tractor had been welded and then ground with a hand grinder. Even the injector lobes! Not good! It ran but was lazy. Thought the valves were just out of adjustment and injectors needed cleaned. I noticed the pumps were out of time, couldn't get them adjusted right....pulled the cam. Wow! Had to find a good used one.

You never know what you'll find on these old tractors.
 

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