Locktite needed on 3535 Plunger Bolt?

[GoBuckeyes]

Hi everyone,

I noticed that one of our Cat3535's was dripping water from under the head so I checked the oil in the crankcase and of course it was milky white, indicating water. We figured one of the o-rings on the end of the plungers was bad but discovered that the bolt had come loose and the plunger was loose as well. We relaced the o-rings, tightened the bolts, reassembled and changed the oil. Then I thought, should we have used locktite on that bolt?

 

[MEP001]

Cat used to have the service manuals on their site but I couldn't find it to confirm. Anyway, I believe it says to use blue Lock-Tite on the bolts. It certainly won't hurt, especially when it managed to work loose.

I'd recommend changing the metal washers and the bolt itself if you pull it apart again.

 

[ken-pro]

Definitely use 242 Loctite (Blue - Medium Strength).

The torque spec is 18 Ft lbs. for those bolts. Too much torque will split the ceramic plunger, BUT 18 FT lbs. will not hold the bolt tight forever without the help of Loctite.

This info is taken directly from the 35 Frame service manual:

http://www.catpumps.com/products/pdfs/35FR2Svc.pdf