Just bought a '85 Thomas school bus with 3208T (pusher). Been sitting for 8 years or so but started and ran to get home ok. Following that, it refused to fire. Turned out to be a seized/gumed pump metering collar (#1) holding the govenor shaft 'off'. Removed, freed up and re-fitted. But have a problem with the cross-over lever on the governor shaft. When i removed the IP top plate, i noticed the cross-over lever cap screw was missing it's head and washer (fortunately found both parts). This allowed the lever a little free movement on the shaft. So cap screw replaced BUT need to syncronize the 'slave bank' with the govenor side bank before tightening the lever screw. I've got the service manual with it's 'War-n-Peace' list of special collars, guages, pins, whistles + methods of checking/calibrating the whole shebang. Groaaaan! However, from what i can glean from the instructions, i should be able to 'short circuit' most of that. I figure the govenor side is good because none of the pump lifters that side have been touched. The slave side neither, so ...... Question: .... can i remove one pump from the govenor side and one from the slave side then get a precise measurement down the pump hole (pump housing 'land' to lift lever), then set the slave side to EXACTLY the same height then lock the cross-over lever? (I have dial guages etc.) .... has anyone done 'home made' methods etc. On these things? Is Nige still Open All Hours?
As for the puller if it is a simple disc with three holes around the out side and one threaded in the center why not just make one out of a disc of say 1/2 plate drill and tap the center hole or weld a nut on after drilling the hole.
Unfortunately, the unit is a distance away so i was hoping to get something together b4 the next trip to it. Hoping for measurements from someone to fabricate something suitable. Thnx for your suggestion.
I just used a small puller and some long bolts
What's the plan for the engine? I'm not sure if I understand the procedure, it sounds like you're synchronizing racks on two banks of a v type injection pump. And this is based on measuring the individual cam lifts? The biggest problem is two cams will never be at the same point at the same time. All eight will be on a different phase. If it's a different procedure, you can ignore this. I'd wing it if the engine is just for putzing around for now while you figure out the rest. Try one way and see if it sounds right, mark it, then move it one way, see how it sounds, move it the other way and see how it sounds. I was going to say spill time it with it's opposite cylinder, but I don't know how an opposite cylinder would work on a V8 (on an inline 4 or 6 the opposite cylinder will be on the same throw so fire 360 degrees around, so at the same point)
Yes, V bank IP. According to the official CAT service manual, a special 'tool' is inserted into the housing following removal of a Pump Unit. This tool is clamped down to the Housing 'Land' and movable part engages the Metering Sleeve Lifter for that particular Pump on the Governor shaft. A dial guage is attaced and locked to the tool. The moving part of the tool acts on the guage to measure the distance between the Pump Housing 'Land' down to the Metering Sleeve Lever. Once this arrangement is set, and the guage zero'ed, it can be transferred to another Pump position and a comparison measurement taken (and an adjustment of 'that' Pump Lever conducted if needed). On a complete rebuild setup, several special tools are required to get a first-base setting. I don't need to do that (nor can i 'cos i don't have all the 'stuff') because none of the stettings for the Governor Bank Lifters has been altered. More on adjustment ..... As far as i understand, the Cam lift is not measured, just the Lever height. I assume from this, the Housing 'Pump Land' machining is a precision process relative to the Cam bore. Also, the individual pumps must therefore also be dimensionally precise relative to each other. Nowhere in the setup process can i see any reference to Cam lift nor radial position during measurement or actual adjustment. I guess the only real test for good adjustment would be to spin the thing up on the bench and comare actual fluid output from all 8 pumps. It's a darned good thing this bus is just a 'fun' project AND having the time ..... being retired Anyone .... please let me know if i've got the "wrong end of the stick" (the 'thick' end?) Thnx
I may be in left field because I don't know the insides of a 3208 pump. Every pump I've seen either the plunger or sleeve rotates to adjust volume. In rotating it also affects timing because it varies the closing of the spill port to start injection, and that is how it adjusts volume, so timing and volume have to match across all cylinders to get them to run smooth and evenly. So I'm not sure what's going on if you're not measuring cam lift or spill port closing based on engine rotation? Really need ThePumpguy, or a cat pump expert.
U can use the method as posted in your # 1 post, as long as both cylinders checked are at the bottom OR the top of its stroke.. Don’t try to use multiple cylinders because they’re all set a smidge differently.. Check 1 and done.. otherwise you’ll be there and moving it till the cows come home.. Good luck
Thank you Senor Pump Guy, I'll 'give it a go as you suggest. I have a question you may know the answer to ..... If i replace an individual pump unit (9N7527?), would calibration be necessary? or are they all pretty much EXACTLY the same? (practically speaking). There's quite a few being sold on places like Ebay which seem inexpensive. Any experience/thought on these? ..... (and yes, 'Chyna' origin!) P.S. The IP is still on the bus some distance from my home .... so ..... i just splashed out $200 on a 'core unit' to dink around with. It'll be interesting to measure up that one (when it arrives) and see results. Thanks again
Just remember, it’s important the way the metering sleeve goes on the plunger.. Pay attention to THAT.. I don’t have any thoughts on the plungers from Chyna.. never used one..