Rebuilt Engine Break In

[mcleaves]

Hi Folks,

Been quite a while since I popped my head in here. Been a crazy summer with household stuff which resulted in Zero boating .

Anyhow I just installed my newly rebuilt 1995 5.0 EFI Ford. I had some water intrusion back in April from a failed riser and being a 1995 I figured if I tore it down I may as well do it all over. I sent it out to a local machine shop.

Turns out it was probably redone not too long ago and things looked to be in very good shape he said ( I have owned it since 2004, so the rebuild happened before that - very few hours on the engine though). It was already bored .30 over, but the cylinder walls were in very good shape so he was able to hone them an not bore it .40 over.

New pistons, rings, pins, pushrods oil pump, rebuilt heads etc.

What he does is build engines, usually high performance. He only dabbles in marine when they come in. As such he couldn't give me a good number of hours to run for a break in period. If it were going in a car he said it'd be 500 miles. Not sure how that translates to marine.

Also I have been reading about break in procedures and there seems to be a million of them. I've seen everything thing from don't even start it until you have it in the water and then run it like a raped ape, to just "don't idle it".

He said to not run it at idle (I think he also said less than 1500 rpms) for more than a few minutes at a time but keep it under 75% WOT.

How do you manage no idling, or less than 1500 in no wake zones. I launch pretty damn close to the open ocean, but I still have about 10 minutes of no wake.

So, what is the preferred procedure guys? Can I run this in the yard to get it timed etc? Also is there is preferred oil for break in? My manual calls for 30w for regular service, but I have read of a few places using a different oil for breaking and then going to mfgr suggested oil.

Thanks!
M

 

[jtybt]

Re: Rebuilt Engine Break In

Roller cam won't need a cam break-in. Flat tappet hydraulic requires a 20 min at 2000 RPM cam break-in.

Not sure about ford engines but chev's don't directly oil the cam/lifters. They get oil from bleed off from lifter bores and 'splash' from rotating assembly.

The main idea is to run above the pre-plane/high load speeds. Don't run for extended periods at one speed/RPM. Vary speeds. After 5 hrs, do some hard acceleration to build combustion pressures to seat rings. There may be different ring seating procedures for moly filled top rings.

Mostly you don't want to run at too high RPM/temps to prevent glazing the cylinders. Generally you want to break-in at least 20 hrs.

 

[mcleaves]

Re: Rebuilt Engine Break In

Thanks Charlie,

This engine is setup a bit odd apparently. There is no roller cam even though the lifters look to be for a roller cam. At least that is what the engine guys said. My cam was in good shape so he suggested not changing it if that is what OMC put in there

So what is the line on running it in the driveway to set the timing, and special oils during break in?

Guess I'm not gonna be trolling for stripers this fall!

M

 

[Apollo75]

Re: Rebuilt Engine Break In

Well, if the mechanic didn't change the cam --- no worries --- just drive it as normal --- I rebuild my engines and then take them out for a high speed run through the gears --- if it breaks --- something was wrong

Take off hard and slow down a few times --- maybe take the kids out and pull them --- tell them to fall off a lot ---- Just kidding. Need to wash down the cylinder walls with fuel a few times with hard acceleration and then slow down and let them pick up some oil again to seat the rings.

With a new bore to .040 --- the cylinders will be round and the rings will seat in no time.


OFM

 

[mcleaves]

Re: Rebuilt Engine Break In

Hmm Tubing.. Good idea! Kids will love me in Cape Cod Bay this time of year!

The bore stayed at .30. All he did was hone the walls. He said it had been done not too long ago so the walls were in good shape.

M

 

[Apollo75]

Re: Rebuilt Engine Break In

Sorry --- old eyes see .040 and brain assumes things it shouldn't.

Use regular oil for break-in not synthetic --- I see no worries --- change oil at about 20-30 hrs. Then use whatever oil you normally use.

I am sure the mechanic put a good cross hatch pattern and saw that there was no abnormal wear in the cylinders.

Go fishing --- trolling will not hurt

 

[mcleaves]

Re: Rebuilt Engine Break In

Thanks... Good info.

The guy was very helpful and honest (or at least open).. He involved me in every step. Had me down the shop every day almost to let me watch the process. Reviewed each component with me as to it's health an serviceability, so I saw the cyls before and after honeing. He went over each one with me as to it's state and how true it was.

M

 

[jtybt]

Re: Rebuilt Engine Break In

Did he install new rings and main/rod bearings?

 

[mcleaves]

Re: Rebuilt Engine Break In

Did he install new rings and main/rod bearings?

Yes, he did.

 

[Don S]

Re: Rebuilt Engine Break In

Still got that disc I sent you a few years ago with the manuals on it? If so, dig up the engine manual and look at page 1-18. It give a fairly detailed list of what to do. If you don't have it, let me know and I will post a link to it.
While you don't have breakin oil, the main thing is not to use synthentic as mentioned earlier.
Gettin a might late in the season for boating isn't it?

 

[jtybt]

Re: Rebuilt Engine Break In

They require a proper break-in procedure. If your machinist used the old cam and lifters, they're probably good to go. New bearings need to establish a wear pattern before excessive loads are put on them. That's why you run them above the pre-plane speeds for the bearings and to make sure you have good oil pressure and volume going to everything.

Break-in procedure also requires checking for oil and water leaks on initial start-up and during 'shake-down' cruise. Monitor oil and temp closely during break-in.

I also run with engine hatch open during first 20 hours to listen to the engine.

 

[mcleaves]

Re: Rebuilt Engine Break In

Still got that disc I sent you a few years ago with the manuals on it? If so, dig up the engine manual and look at page 1-18. It give a fairly detailed list of what to do. If you don't have it, let me know and I will post a link to it.
While you don't have breakin oil, the main thing is not to use synthentic as mentioned earlier.
Gettin a might late in the season for boating isn't it?

Have I told you how much of a PITA you are sometimes .

Thanks!! I showed Todd your post. He took the manual off the shelf (yes I have the disc AND a complete set of pretty blue manuals) and opened it to that page, then looked at me like I was an idiot. He want to know why you let me off that easy

Yeah it's late to get started, but I just dumped some coin into this engine and I'd rather know if it runs now than try to argue about it in the spring. Besides, it's still beach weather here

M