CAT 7155 Manifold rebuild

[R Racing]

Ok after reading the Cat manual ( SENR7002) a total of 7 times,LOL I decided to build a test unit for the Cat 7155 transmission.I tested a few Trannies I had here and found 2 with Manifold issues.( The most common issue with the transmission) I went out in the lovely rain and pulled the manifold off of 1 of the trans, And proceeded to clean and dismantle the manifold. Here are some pictures.

 

[R Racing]

I have a e mail in to Cat to see price and availability on a rebuild kit . This head was full of gunk inside. I'm testing a upgrade for the 7155 that I believe will add years to its life. More on that in a week or so. I would say skill level on this on a scale of 1-10 is a 10+ LOL. there are more O rings and poppets and seats in this thing than you can shake a stick at !

 

[Monkeyboyarmy]

Where is that darn popcorn smilie at!

 

[NSCoyote]

subscribed for updates. and thanks R racing

 

[swbradley1]

I watched Doghead load your transmission at the rally. Big is all I can say.

 

[R Racing]

I have a 2nd 1 to rebuild after this. I still need a 2:1 or 3:1 gearbox to test under load . I like the trans to much to change to a full stick , And hope to be able to keep them living for years to come.

 

[R Racing]

I watched Doghead load your transmission at the rally. Big is all I can say.

Yeah there fun to swap out thats for sure ! LOL Swapped 1 out on a m917. May have to do the same on my m920 soon. there around 1100 lbs and there is a ton inside.

 

[NDT]

Momma lets you rebuild transmissions on the dining room table???

 

[R Racing]

No momma here lol just a daughter and 2 dogs. and thats a 6 foot folding table from the basement. lol

 

[eldgenb]

yep if mine ever goes, I have an eaton fuller 15 spd on standby, you are much braver than I am, keep up the good work.

 

[wreckerman893]

It really PO's me that my buddy scrapped two of those trannys.....Jim got the shifters off them but most of the rest of the two trucks are on a slow boat to China by now.

By the way....Jim is a stand up guy....I bought a 12 volt fuel shut off for my M915 by mistake and Fleetpride does not have the 24 volt ones. Jim is sending me one of his spares so I don't have to shut it of manually every time. Thanks again Jim.

 

[R Racing]

yep if mine ever goes, I have an eaton fuller 15 spd on standby, you are much braver than I am, keep up the good work.

If you ever go that route I'll take the Corpse lol.


Any time WM Your Good people! and from what I hear can do Amazing things with cooking Possum !!! Wish I could have grabbed those 2 Trans . I'm hoping to have some good rebuilds after all of this that work, and may be able to keep these trucks on the road and away from the scrap heap.If anyone knows were any dead or forgotten Cat 7155s please let me know. Parts from Cat I'm finding are Gold Plated but available.Unfortunatly a few of the O rings and the Manifold gaskets are none standard and only available from them. Hopefully I will have a update from Cat Tomorrow.

 

[Ord22]

always wonder what the insides look like. thanks for the inside look!!

 

[R Racing]

always wonder what the insides look like. thanks for the inside look!!

Your welcome ! Its actually a ingenious design that has many safetys built in. Today was a bit confusion for the cat dealer , but they say there on it . we will see ???

 

[R Racing]

Well I did hear back from Cat and it appears everything I need is in stock. Its just CAT EXPENSIVE !! LOL I will keep you posted . I have the Main valve assy back together waiting on shift seals and some odd size O rings and a few gaskets.

 

[Hammer]

I hate to ask, and I am familiar with CAT's pricing, but what kind of quotes where they throwing your way?

 

[R Racing]

Well for 5 gaskets. Some O rings ( around 80 in total) about $1600.00 LOL I have been able to find most of the O rings thru other sources but there are 13 of 1 type and 3 of another that are none standard size.So I'm still looking at near the $700.00 range for those with the gaskets.Was told any labor would be $116.00 a hr I believe. but I'm hoping to rebuild the manifold and have them do the swap.

 

[Hammer]

Wow, I bet it would be cheaper to have those orings custom made for you!
Obviously the gaskets seem like something that could only be supplied through CAT.

Great pictures so far. Keep up the good work.

 

[R Racing]

Thank you ! Unfortunately camara #2 bit the dust so off to BB in the am to turn both in for repair. The manifold is going back together and I still have 2 more test tools to make. Hopefully I will have it on the test bench on thursday . If it works then I only will have 3 more to go !!!!! LOL

 

[NDT]

Seems to me that if your transmission is an original 1979 unit, the o-rings must be shot or close to it.