Gehl 4835 relief valve

[oldandrusty]

I am new but have gotten really good intel from other equipment forums as it seems most true mechanics are hard to find anymore. With that in mind, I have a 4835 with about 1300 hours on it and now it has started something I can't figure out and the dealer isn't too sure where to start either. Every so often, like the other day, I'll start it to warm it up and all of a sudden the engines comes under what I would consider the response to a heavy load and smokes a bit and powers down for a little bit then will return to normal idle and may do it several times. I thought maybe it was just cold but it is kept inside in heated space. It hadn't done it for several weeks. I did what I needed to do with no problems and everything was fully warmed up and as I was getting ready to put it back in the shop it did it again, several times, just sitting and idling. My question is could a relief or bypass valve in the main hydraulic pump be causing this. It sounds and acts just like they do when you have cylinders fully extended or contracted and the bypass has to kick in when you reach the end of your stroke. The shop foreman said, could be, maybe blower, etc. Don't think it's the blower as it would be more consistent and I would think noisy. Thanks in advance.

 

[BigD2251]

oldandrusty, what did you find wrong or what was the cure?

 

[oldandrusty]

oldandrusty, what did you find wrong or what was the cure?

Well, I contacted the dealer and they gave all kinds of different answers from worn wash plates, to bad drive motors????, to on and on. asked about a bad main pressure relief valve and was assured by several mechanics that, that wouldn't be it. Not liking their ideas and having some background in hydraulics, I contacted a friend who is an excellent mechanic and has worked on just about everything at one point or another. He agreed with me the main hydraulic pressure relief valve I was suspecting was the place to start, and guess what? Wala, that was it. So much for the dealer and their mechanics. $180 later all fixed. Seems to be the way of parts changers these days, not as many mechanics as there used to be.

 

[foton]

could not agree more. it seems that younger mechanics need a computer to tell you what parts to change anymore.