engine break in

kawzx10

Active Member
Location
Layton,UT
Hey guys I got a question for you guys with non street legal vehicles or buggies. I just got my engine rebuilt Im trying to get it all put back in the truck for jeep safari. I have been doing some reading on breaking in a rebuilt motor and its saying like 500 miles. My rig wont be street legal so its not like I can just take it easy around town. What do you guys do to break it in just take it easy on the trails or what? I dont want to screw anything up after spending all this money on it so any info would be helpful. Also just for a little info on the motor its pretty much just a stock rebuilt 77 dodge 440. Thanks Zack.
 

zukijames

Well-Known Member
Location
not moab anymore
im in the same dilema. im getting a 22r built from zukiengines.com i plan on running propane .. but you cant break it in on propane..

so i'll have to buy a carb $ then try to figure out how to do 500 miles since im not street legal.. and dont have a trailer.. then ditch the carb and buy a gotpropane kit $$

hopefully someone has some good sugestions for both of us
 

kawzx10

Active Member
Location
Layton,UT
Oh man dont say that I guess I should have done more research. I just sold my carb and was getting ready to order the gotpropane.com kit. I may have to run my taco. My wife isnt to happy about all the time I am spending on this project just to beat up my dd.
 

Grim

Well-Known Member
Location
Roy, UT
how many hours would it take you to drive 500 miles?....start with low RPM , work you way up , change oil often
 

DOSS

Poker of the Hornets Nest
Location
Suncrest
If you want you could always set up some kind of electic motor to do the break in for you.. a couple horse motor hooked up to the engine, no spark plugs.. run it for a few days straight with different RPMS and a couple oil changes :)
 

BCGPER

Starting Another Thread
Location
Sunny Arizona
I'm curious who it was that said you can't break an engine in on propane. How do you think we break in propane fueled engines? :D

Break it in on the fuel you intend on running. I usually break in the engines I rebuild for an 8 hour period at varying loads. After that period, it's full load 24/7, with the first oil and filter change at 500 hours.

Since you're not street legal, take it out for a day on some two track trails around here and just drive it for a day. Do that a couple times then change the oil and filter and you should be good to go.
 

4554x4

always modifing something
Location
Sandy Utah
FLAT TAPPET CAMS

That 440 will have a flat tappet cam unless you went to a roller cam. I guarantee you will ruin your engine within 500 miles if you use todays oils. The Feds want increased gas milage from all the new cars as well as low emissions. They have required this from the manufacturers. In order to acheive this they expect allot from the Catalytic converters that will be poisioned from the zinc and phosforus that used to be in the oils. The zinc and phosforus helps the high friction areas of the engine, especially the cam and lifters. I have witnessed how quickly a cam can go flat, thus polluting the entire engine with debris, then completely starting over.

The only product that I am aware of is Joe Gibbs Racing Oil and Assembly lube. Check with Glen at Parts Connection at 801-572-0272. He will be happy to expound on what I have said.
 

kawzx10

Active Member
Location
Layton,UT
I just got off the phone with gotpropane.com. They said its fine to break in on propane unless you have chromoly piston rings. They also said if your engine builder is telling you to do certaint things you should do it the way they say.
 

oldjpr

New Member
The Joe Gibbs Racing oil is a great way to go, but another alternative that I found after wiping out the new cam in my 1969 Big Block Chevy Truck is a zinc additive from Summit Racing. You can find it on their website. Like 4554x4 mentioned the zinc has been taken out of modern engine oils to protect the catalytic converter. You must have a minimum level of zinc during the break in period to avoid failure in the high stress areas such as cam and lifters. Talk to Parts Connection and do some research on Summitracing.com and you will learn how to protect your investment. Since you said it is not street legal I imagine you don't have or don't care about damage to a cat from the zinc. My son and I are finishing a new engine in his Scrambler and will trailer it to Moab or St. George for a few days of easy trails, then change the oil and filter and be back for the Jeep Safari. A couple of hints, Don't lug the engine during break in, it creates too much heat. Avoid high RPM during break in, above 3000 RPM should be limited to short bursts. Try to vary the speed as much as you can so the engine experiences the full range of cylinder pressure to fully seat the rings without generating too much heat or friction. Keep an eye on oil pressure all the time, engine temp must be in the normal range and get the fuel system as dialed in as possible to avoid running either rich or lean. Make sure you set the timing and prime the fuel system and prime the oil pump before you start the engine for the first time. If it cranks and cranks and cranks it can wipe off all the expensive cam and lifter lube the engine builder put on there to protect these high pressure contact surfaces. Get it running and hold at high idle, 1500-2000 RPM for 25-30 minutes so the cam can be kept cool and bathed in oil during the initial startup.

Send a PM if you have any additional specific questions. Happy trails.
 

4554x4

always modifing something
Location
Sandy Utah
The Joe Gibbs Racing oil is a great way to go, but another alternative that I found after wiping out the new cam in my 1969 Big Block Chevy Truck is a zinc additive from Summit Racing. You can find it on their website. Like 4554x4 mentioned the zinc has been taken out of modern engine oils to protect the catalytic converter. You must have a minimum level of zinc during the break in period to avoid failure in the high stress areas such as cam and lifters. Talk to Parts Connection and do some research on Summitracing.com and you will learn how to protect your investment. Since you said it is not street legal I imagine you don't have or don't care about damage to a cat from the zinc. My son and I are finishing a new engine in his Scrambler and will trailer it to Moab or St. George for a few days of easy trails, then change the oil and filter and be back for the Jeep Safari. A couple of hints, Don't lug the engine during break in, it creates too much heat. Avoid high RPM during break in, above 3000 RPM should be limited to short bursts. Try to vary the speed as much as you can so the engine experiences the full range of cylinder pressure to fully seat the rings without generating too much heat or friction. Keep an eye on oil pressure all the time, engine temp must be in the normal range and get the fuel system as dialed in as possible to avoid running either rich or lean. Make sure you set the timing and prime the fuel system and prime the oil pump before you start the engine for the first time. If it cranks and cranks and cranks it can wipe off all the expensive cam and lifter lube the engine builder put on there to protect these high pressure contact surfaces. Get it running and hold at high idle, 1500-2000 RPM for 25-30 minutes so the cam can be kept cool and bathed in oil during the initial startup.

Send a PM if you have any additional specific questions. Happy trails.

Couldnt have said it better!
 

oxbronco

Active Member
I also used joe gibbs assembly lube and oil for the break in for my 460. And got it from parts connection. Been very happy with the joe gibbs break in and motor oil
 

MikeGyver

UtahWeld.com
Location
Arem
The 'correct' way to break in a motor is to run it HARD.
You only have a short while of the coarsest crosshatch on the cylinders and you want to make full use of this filing action to seat the rings. Running an engine hard and letting it decelerate hard keeps load high and vacuum high. Make sure the engine is completely up to operating temp first and keep a close eye on all critical engine readings. If you put-put around under little or no load for too long you've lost a lot of crosshatch and have risked the rings not seating. If you're running a flat tappet cam I believe they have special precautions.

Many people seem to to be worried their new motor will break if they run it hard. This is a pretty silly idea, if it does break then something was wrong to begin with. Race motors aren't usually 'broken in', they're just run flat out.
 
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neagtea

Well-Known Member
Supporting Member
Location
farmington
Break in the cam and thrash away. Lots of additives out there I am sure royal purple or redline has one. Also, Joe Gibbs oil = good to go. recomended by many builders
 
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