D4H - 3204DI inframe Rebuild

[N00bie]

Might not be the appropriate forum, but I don't see one for engines.
Engine 3204DI when hot and working, pushes oil out of the dipstick. Not a little, like a gallon per hour!
Have motor disassembled. Since the motor is sleeved, must assume it has been rebuilt.
Here is the question:
I understand there is an upgrade piston available - 3 ring.
Does anyone have any experience with these pistons?
Are they any good? Are they cheap Chinese crap?

Because the 3204DI pushes the outer limits of the engine (99 horse) and rings are known to fail, thinking about these 3 ring pistons.

Ant insight would be helpful. Thanx

 

[OzDozer]

The IPD 3 ring pistons are reputedly the best you can install in the 3204.

IPD even started to brag about their pistons being better than Cat pistons, but they stuck their neck out a little too far, and Cat sued them and won!
IPD had to back down on their claims, and it cost them some serious $$$'s.

Despite that, general user feedback seems to back up what IPD claim.

I'm currently doing an out-of-frame overhaul on the 3204 in my 931B.
The engine is completely original, but the Cat 2 ring pistons have fractured at the skirt.

This is only a 65HP engine, and I have no idea of the total hours it's done, but I believe it's likely to have done around 8000 hrs at least.
The tractor has worn out one set of undercarriage, and the replacement undercarriage is nearly worn out, too - so that's how I'm estimating the total hours.

I have the engine right out and totally disassembled, and I'm doing a full out-of-frame rebuild.
Accordingly, I have a full IPD 3 ring piston engine overhaul kit on its way.

I'm just waiting on the engine rebuilder to advise the amount of overbore required, the bore is currently standard. Hopefully, I'll get away with .020" oversize pistons.

Use only genuine Cat wrist pin bushings (little end bushings) as I've been advised by more than one end user and repair shop that the genuine bushings are the only ones that hold up.
These bushings are a weak area for the 3200 series engines, Cat redesigned them more than once.

 

[Welder Dave]

The 3204 in my 931B has .010" over size IPD pistons in the bored out block. It starts instantly and has a little more power. No complaints at all. IPD has up to .040" oversize pistons for 3200 series engines. Would be interested to know why the OP's engine was sleeved?

 

[N00bie]

Will need to call IPD tomorrow as they list nothing for the 3204 on their website/store.
This dozer has a documented >25,000 hours and that is from CAT.
Have seen no physical damage to anything. Having someone come out to look at the pistons, sleeves, etc
The rod bearings are all STD. Not sure if I am going to replace the main bearings - dont like fixing things that are not broke.

I have noticed many companies selling 3 ring piston upgrades for the 3204DI, such as dieselrebuildkits.com, agkits.com, and others. Not interested in Chinese parts. Would go CAT but they don't make a kit and would have to piece it.

 

[Welder Dave]

Look under 3208 pistons. IPD lists 4 different styles of pistons. 3204 is half of a 3208.

 

[OzDozer]

The parts are generally listed under "Cat 3200 series" engines, as the 3204 and 3208 share a large amount of common components.

 

[Welder Dave]

I noticed on the IPD site the part numbers have 3208 in them which might be why it's more difficult looking under 3204. Regardless it looks like they are available.

 

[AllDodge]

Rebuilt mine by boring and sleeve to original size

 

[OzDozer]

Sleeves are an extra additional cost, but if the engine has been sleeved previously, then I'd have to say you have no choice but to install new sleeves.

The standard parent bore has enough metal thickness for a .040" oversize rebore.

I'm surprised Welder Dave was able to acquire .010" OS pistons, it seems IPD are now only supplying .020" and .040" oversize pistons for the 3200 series.

The ugly part of the 3204 rebuild is the cost of an oil pump rotor! Around US$500 it seems.
I'm taking a closer look at my oil pump rotor, I'm starting to think it looks good enough to re-use at that kind of replacement price.

There's no scores or serious wear in my rotor, just a tiny amount of wear on the top of the lobes.
I have yet to check the allowable rotor wear, but it appears it's no more than .006", which I think would be acceptable.
Older Cat engines rely on oil volume, not pressure, to keep things properly lubed.

 

[Welder Dave]

When my engine was done IPD had .010", .020", .030" and .040" oversize pistons. My oil pump met specs. and showed very little wear but 16 1/2 hours after the rebuild heard a bang and lost oil pressure. One of the teeth on the gear that drives the oil pump broke off. Shop said after that they would never reuse an oil pump again on a rebuild. Was covered on warranty but still had to pull engine and trans. out again.

 

[N00bie]

Thanx for all the input, but now down to the wire...

The whole problem was the head (#4 piston values) - they were hitting the piston.
Anyway with engine apart:
Have only owned since 2017 and have only put on 500-600 hours on the farm. Engine obviously was recently completely rebuilt (Engine has 25,000 hrs according to CAT): cylinder walls still has hash marks, everything standard, could reuse piston rod bearings if I wanted to, etc. Rebuilding anyway since apart.

Question is: Told by one company that IDP pistons are hard to get there days and recommended using Interstate-Mcbee 3 ring pistons and rings. Another company says no problem and can put together an IDP rebuilt kit with 3-ring pistons pistons from Ohio and gaskets from California. The difference in cost is double: McBee about $1,000; IDP about $2000.

More money does not always mean better and, if I go with the $, how do I know the pistons and everything is really from IDP?

Thanx

 

[Acoals]

The valves were hitting the pistons? Why?

 

[N00bie]

The valves were hitting the pistons? Why?

Not the question i am asking, but there were no guides, sleeves, seals, etc. The exhaust valve was so sloppy that under load it would twist and hit the piston thereby causing all the blowby. There was enough of a problem for an $800 valve job!

 

[Welder Dave]

How does Cat figure the engine has 25,000 hours. That's seems high for a 3204 unless it's been rebuilt a couple times already. I wouldn't think IPD pistons are hard to find. I'd guess that company doesn't deal with IPD much. I can vouch for IPD in my engine. I've got about 1800 hours since the rebuild. Sometimes you have to trust the shop and they should warranty their work. Why would they use different or possibly lower quality parts? You could ask to see the boxes the pistons and other parts come in.

 

[Welder Dave]

Not the question i am asking, but there were no guides, sleeves, seals, etc. The exhaust valve was so sloppy that under load it would twist and hit the piston thereby causing all the blowby

Sounds like you need a new cylinder head. Are there signs of loose metal pieces causing other damage? Maybe the engine was slapped together just so it would run to sell it??

 

[heymccall]

The exhaust valves were so sloppy in my 5k hour D4H that the soot accumulated on the oil pickup tube. This resulted in a low oil pressure warning at throttle up. You could get black smoke out the oil filler when the fill cap was removed and the engine throttled up.

Machine shop said the valve guides were just bored into the cast iron, no sleeves. It now has sleeves.

 

[N00bie]

Lots of comments, none of which address the actual IPD vs McBee question.

Have service records from CAT documenting 25,000 hrs on machines serial and motor serial is original. Thus, if machine has 25,000 hrs, so does the engine. Yes, probably rebuilt several times. Don't need new head. 3204 heads don't have sleeves but can be repaired with sleeves. Machine not lapped together as a 25,000 hr engine with ALL standard bearings (obviously new crank) and pistons. No metal in oil pan.

Anyone know about McBee?

 

[Welder Dave]

The only way to compare the pistons is if someone has either rebuilt engines using both or a machine owner has ran engines with both. There are a few other threads on here where mechanics and/or users have praised IPD pistons and parts. A few not so good reviews reviews for Mcbee online but you could call a shop like below that sells both. I'd suspect the IPD to be higher quality for the extra $1000. IPD appear to be made in USA and Mcbee may come from China but apparently some OEM Cummins comes from China so it may not make a difference where they come from as far as quality.

About Us

About Diesel Rebuild Kits At Diesel Rebuild Kits, we have over 30 years of experience in the heavy duty diesel industry. We are distributors of high

www.dieselrebuildkits.com

 

[N00bie]

The only way to compare the pistons is if someone has either rebuilt engines using both or a machine owner has ran engines with both. There are a few other threads on here where mechanics and/or users have praised IPD pistons and parts. A few not so good reviews reviews for Mcbee online but you could call a shop like below that sells both. I'd suspect the IPD to be higher quality for the extra $1000. IPD appear to be made in USA and Mcbee may come from China but apparently some OEM Cummins comes from China so it may not make a difference where they come from as far as quality.

About Us

About Diesel Rebuild Kits At Diesel Rebuild Kits, we have over 30 years of experience in the heavy duty diesel industry. We are distributors of high

www.dieselrebuildkits.com

Thanx for addressing the McBee-IDP issue. Had tried to deal with diseselrebuiltkits but never got a response from them. Called them this am and they said that IDP was definately the better quality. They are supposed to give me a quote on a McBee and an IDP kit. We shall see ...

 

[OzDozer]

I have had no problem sourcing new .020" O/S 3 ring IPD pistons here in Australia - but I have had to wait for them to come from the U.S., which has taken around 3 weeks.
They weren't normally stocked here in Australia. They should be in my hands at the end of this coming week.

The cost was quite reasonable, AU$720 for a set of 4 IPD pistons (about US$470).
All up cost of the Out of Frame Kit was AU$1670 delivered to my door (US$1088).

This figure does not include wrist pin bushings, which I am sourcing from Cat. General advice is, DO NOT use any other wrist pin bushings except genuine Cat, as aftermarket bushings fail early.

Ensure the wrist pin bushings are installed exactly as specified in the Cat service manual.
The bushing to pin clearance is critical, these bushings are the weakest part of the 3200 series engine.

These engines are getting old now (they first came out in 1973), and I believe IPD may be cutting back on production of older engine parts such as these pistons.

The general information I have gleaned is that the IPD products are superior to all the other aftermarket parts, and the vast majority of the IPD parts are still made in the U.S.

Interstate-McBee do not have the same reputation as IPD and I understand a large proportion of their parts are manufactured in China. The Chinese QC is still as suspect as it ever was, and there are plenty of contributors to forums stating they haven't got satisfactory life out of Interstate-McBee components.

The very fact that Interstate-McBee can supply parts/components at exactly half the price of IPD parts/components should ring alarm bells for anyone.
It's an old truism, I know, but you generally get exactly what you pay for.