Hi Yall,

I'm new to the board and new to diesels.

I am looking into purchasing a CTD 2500. One of my big questions is how do I determine a good engine / truck from one that should be left alone.

I am leaning towards a 1998 - 01 2500 cab+ 4wd manual with about 150k. Prefer a HO 6 spd but will depend on the deal. I see lots of nice trucks with good prices out in TX but not sure it is worth the trip.

How can I see compression or lack of on a Diesel? Is their a way to measure blow by? Should their be Zero Blow by. Any quick way to test a used truck for fueling issues?
Any way to load test or check the fuel system on a test drive with no guage.

What kind of damage would a CTD show if run hot? Head / head gasket like gas motors?

I'm rearding a few hrs a night trying to get caught up. VP-44, Lift Pump, KDP, 5th gear nut, ect.

Thanks,
Michael

 

You need a blowby tool. a blowby orifice tool is simply a tee with one .221" (15/64-in) outlet. Connect one end of the tee to the end of the blowby tube. Put a manometer on last tee outlet. That is your blowby tool. They sell them at the Cummins, but I have made my own plenty of times. A simple manometer can be made by looping into a U 6' of clear tubing with water in it half way. Measure how high the water level rises with a tape measure, multiply it by 2, convert it to LPMs

Rough conversion is1"= 27 lpm, add 3 lpm for each one inch (1/2'' of rise in the tube) of water

New engines numbers are;
63 liters per minute(2.5" water rise = 5" of water) @ 2200rpm,
76 L/Min (3.5" rise) @ 2500rpm
85 L/Min (4.5" rise) @ 2800rpm.

Worn engine that needs rebuilding are roughly double i.e.
126 L/Min(10.5"rise) @ 2200rpm
152 L/Min(14.5"rise) @ 2500rpm
170 L/Min(17"rise) @ 2800 rpm

The valves could also be out of adjustment.

Another way, same idea, is to block the blowby tube with a 1/2'' pipe nipple with a cap that has a 15/64 hole drilled in it. Use 3/8'' id looped clear tubing with water in it slipped over the oil dipstick tube. Use sharp tipped felt marker to mark the water level with the engine off, have someone start an already warmed up engine and run the rpms up to 2.2, 2.5 & 2.8k rpms. Mark each water level with the pen, measure then multiply each by 2.

This is all very simple to do, just hard to explain with words.

 

Can I actually measure compression thru the injector passage on a Cummings?

I was looking for a Blowby tool on Ebay and ran across this Diesel Compression tester. THe description mentions Cummings but not which models.

Diesel Cylinder Compression Tester Unused 1000 psi


Description


Welcome! Be sure to check out our other auctions, and don't forget to click the "me" by our name to see photos of our store!

Unused government surplus

This compression tester came from a government truck tool kit for the large trucks with the cummins and mutifuel engines
Winner pays shipping. Good Luck!



http://cgi.ebay.com/ebaymotors/ws/eB...552638653&rd=1

 

say it with me, cummins. no g

 

I'm saying it, But still trying to wrap my head around the ideia. Diesel is new to me, and want to be certin of my investment.

I'm not comfortable buying one 150K with out knowing a little more about the internal condition. They gotta be selling it for a reason, Right? I've got 7 years wrenching on small gas imports, so the standard practices I've been living by will be hard to break.

 

150K is not a problem for the engine.. Typically you run into other gremlins on the truck far before the engine fails.. Track bar, ball joints or other drive train related wear parts.

I would put my attention into the fuel system. Check for Codes that would indicate pump timing failure and have the lift pump pressure checked. Also look at the electrical connections to the pump for signs of tampering that would indicate a plug in box of some sort. Typically head gasket failures or engine wear problems are related to fuel increases from aftermarket items. Stock engines shouldn't be a problem.

The blowby test is really a good indicator of bottom end wear, but compression gives you a more complete picture. The heads are a higher wear concern than the lower end. But again at 150K, it shouldn't be a problem.

It sounds like you have done alot of reading and are pretty well versed in the CTD, more than most thats for sure.. Good luck on the search..