New engine questions

[mtnrat]

I just put in a new longblock 350 and changed from 2bbl to 4bbl. I got a q-jet from i5automotive. Some of you who have been following may recognize the swap from a 305 to a 350. Runs very smooth in the driveway. What I would like to know is what is the proper breakin proceedure for my 18 footer and this new engine.
Thanks

 

[Reel Poor]

Re: New engine questions

Just don't run the engine to hard for 20 hours. While running, vary the cruising speed rpms up and down some. Don't stay at one throttle setting for long periods of time. Then when you do hit WOT (after the 20 hour period and oil & filter change) just do this for "short" runs, then pull back to normal cruising range.

 

[mtnrat]

Re: New engine questions

Thanks

 

[aggiedave98]

Re: New engine questions

do some google searches for breakin... but in general it's don't push things too hard and vary the rpm's. I used to think it was an overkill until I started to read engine books that I'm using to rebuild my suburban 350...

in cars/trucks, you also don't want to tow in the first 500 miles, so basically, the less strain on your engine, the better.

good luck and keep the rpm's different and don't max it out....

 

[DHPMARINE]

Re: New engine questions

Yep,a new or rebuilt engine have similarities.Main thing is all the surface have high and low spots,This includes bearings,pistons,cylinders etc.

Your choice here,break it in HARD and pound these spots into the sufaces they ride on .....

I'd go easy,and scruff off the high spots gently

DHP

 

[mtnrat]

Re: New engine questions

Took it out today for 3hrs. Took it easy out of the hole and drove around for 3hrs. Very easy for the first 1/2 hr (2500rpm max), then up to 2800, then to 3000, then to 3200 and finally maxed out at 3500. Varying the throttle speed every 3 to 5 min. It was smooth and worked like it should. Temp about 170 and oil pressure about 52.
Mtnrat

 

[Reel Poor]

Re: New engine questions