Rebuild break in

NH3tech91 · **Joined:** Mon Apr 01, 2024 5:18 pm **Posts:** 9

Haven't fully combed over the manual for the information but wondering if anyone has some recommendations when it comes to a break in for a full rebuilt motor. I was going to do oil plus filter change every 500 miles for the first 3k then normal intervals. The EGR has been disabled and I think the ecm has a tune not sure. Check engine light never came on previous engine and no codes for EGR was on it either.

DieselJeepLuvr · **Posted:** Sun May 19, 2024 11:44 am

If it was done right, you should be fine just changing the break in oil after 500 miles. I'd use Delvac 15W40 initially since a thicker oil will carry impurities to the pan better. Make sure you watch the engine temperatures closely. breaking in the rings and cylinder walls will produce a lot of friction for the first half hour or so.

Mountainman · **Posted:** Sun May 19, 2024 4:17 pm

Make sure you understand that the break in for diesels is very different than gasser. I just follow the same lengthy procedures that other diesels call for.

*the 'idle the engine for as little as possible' for x miles is extremely important, as is loading the engine.

Read about glazing the cylinder walls if you're not familiar.

- it's all about getting the rings to seal properly to the cylinder walls. Easy to screw up!

NH3tech91 · **Joined:** Mon Apr 01, 2024 5:18 pm **Posts:** 9

Mountainman wrote:

Make sure you understand that the break in for diesels is very different than gasser. I just follow the same lengthy procedures that other diesels call for.

*the 'idle the engine for as little as possible' for x miles is extremely important, as is loading the engine.

Read about glazing the cylinder walls if you're not familiar.

- it's all about getting the rings to seal properly to the cylinder walls. Easy to screw up!

I've poked around most information I could find was for trucking diesel engines and combing through the 2.8l engine section didn't turn up anything. I do happen to live near some hilly roads but sold my trailer a couple years back so I'm not to sure how I'm going to put any load on it other than putting it in low and driving on the hilly roads. Maybe throw some weight on the trunk to help.

DieselJeepLuvr · **Posted:** Tue May 21, 2024 5:33 pm

It's not that complicated. Don't overthink it. Just remember to watch the temperature gauge. If it starts getting hot, pull over, shut it off and let it cool down. Otherwise just take it out for a drive and drive it like you normally would but don't baby it. I'm a 3rd generation diesel mechanic. Trust me. I stayed in a Holiday Inn Express last night.

NH3tech91 · **Joined:** Mon Apr 01, 2024 5:18 pm **Posts:** 9

DieselJeepLuvr wrote:

It's not that complicated. Don't overthink it. Just remember to watch the temperature gauge. If it starts getting hot, pull over, shut it off and let it cool down. Otherwise just take it out for a drive and drive it like you normally would but don't baby it. I'm a 3rd generation diesel mechanic. Trust me. I stayed in a Holiday Inn Express last night.

I was thinking trying to keep it around 1.5k to 2.5k for the first 30 minutes of driving. Not letting it just idle. Think I should keep it under 3k for the first 500miles?

Mountainman · **Posted:** Wed May 22, 2024 11:35 am

I think those rpms sound fine. Just try to gear down on the down hill.
Driving 75ish on a highway with some cargo would be quick and easy. Vary your speeds and load.

And the low gear you mentioned would lessen the load on the engine via more mechanical advantage.

In your situation I would just drive it vigorously, and gear down on the downhill, and preferably hit the freeway with a bunch of passengers or cargo

Mountainman · **Posted:** Wed May 22, 2024 1:03 pm

I should add that I come from the rockies, and downhills last for minutes. So, I wouldn't worry about downshifting on little eastern hills. But, hitting the OD off button can conveniently drop a gear (speed dependent), and that '"dfferent" loading can't hurt to seat those rings. I break in on big grades, and I downshift, and accelerate a little where I can without having to use the brakes more

NH3tech91 · **Joined:** Mon Apr 01, 2024 5:18 pm **Posts:** 9

Mountainman wrote:

I should add that I come from the rockies, and downhills last for minutes. So, I wouldn't worry about downshifting on little eastern hills. But, hitting the OD off button can conveniently drop a gear (speed dependent), and that '"dfferent" loading can't hurt to seat those rings. I break in on big grades, and I downshift, and accelerate a little where I can without having to use the brakes more

I think I'll end up renting a tow dolly and drive around with my friends little sedan on some back roads not far out of town just in case I have and problem I'll be close to home. Thing can't weight more than 3000lbs.

Mountainman · **Posted:** Thu May 23, 2024 10:46 am

I'd do a cam burnishing break in first if you replaced them as well. It's been long time. But thinking 2k for 5 minutes has worked well for me. Watching gauges and for leaks
The trailer towing sounds like good insurance

NH3tech91 · **Joined:** Mon Apr 01, 2024 5:18 pm **Posts:** 9

Hopefully good omen. After getting it back in and everything hooked up it fired right up no problems and quickly loaded it couple 100lbs and ran it hard sounds great and keeps pulling harder. Going to tow with it next to really get it broke in. Thanks for all the suggestions everyone.

NH3tech91 · **Joined:** Mon Apr 01, 2024 5:18 pm **Posts:** 9

When I do the first oil change would it hurt to run motor flush through it before help pull everything down to the pan? I was going to do a coolant flush around that time as well.

DieselJeepLuvr · **Posted:** Wed May 29, 2024 2:22 am

Motor flush is only used to clean sludge out of high mileage vehicles.

Mountainman · **Posted:** Tue Jun 18, 2024 4:12 pm

X2, I wouldn't put anything other than oil in the engine. I'm obsessive with getting break-in particles out, so I do 2-3 premature oil changes in engines that I want to get 300k+ out of. Might be a waste of oil...

layback40 · **Posted:** Tue Jun 18, 2024 9:02 pm

The best thing you can do for the first oil change is to make sure its done straight after a good 50-mile run. Best get ready to drain it before you take it for the run. Jump out of the car & undo the drain plug. You can undo the filler cap & take the dipstick out after you start draining. Remove the filter while its draining. I like to drain into white ice-cream containers so that anything in the oil is easy to see. Its good to also cut open the filter to see what's in it. Expect some minor debris. Bits of nuts & bolts would be a red flag.

DieselJeepLuvr · **Posted:** Thu Jun 20, 2024 2:09 pm

layback40 wrote:

Bits of nuts & bolts would be a red flag.

What about whole nuts and bolts? Those are ok, right?

:ROTFL:

layback40 · **Posted:** Thu Jun 20, 2024 9:49 pm

DieselJeepLuvr wrote:

layback40 wrote:

Bits of nuts & bolts would be a red flag.

What about whole nuts and bolts? Those are ok, right?

:ROTFL:

Probably whole ones would need to get broken up a little before they would come out.
I know of a dial gauge that was found in a CAT D9 sump. The magnetic base had kept it away from trouble.
At 20,000hrs, was surprising, the engine had never been in pieces since new! :dizzy:

Rebuild break in

Who is online