Rb25 forge rebuild smoke

[drifter17a]

All,

 

engine forge rebuild with full balancing however it smokes which is minimal and i think it is due to rich mixture as can smell fuel

 

pcv is to air so manifold return is blocked off.

 When on i can see mist of smoke on idle from catch can which is strange and wanted to seek opinion here before going back to tuner

 

Has anyone here followed the hpacademy as looking to learn and tune the ecu myself . I have purchased their engine rebuild course and it is quite good

[KiwiRS4T]

Did you run it in hard with mineral oil or baby it with synthetic oil? If you don't run it in properly you will end up with glazed bores and rings that don't bed in. Have you measured your oil consumption?

Re the tuning do you have a wide band sensor installed?

[drifter17a]

By run in do you mean inserting piston or bed in?

 

i didn’t do it as tuner did and remember on one of the pics there was fair bit of oil in bore and he said it was the bore oil

 

it has done 300 miles since and expect to return and change oil at 1k ( bed in period)

[KiwiRS4T]

By run in I mean the initial start up and first hour and  first 1000km of running the engine. How did you do it? And what is bore oil?

[Dose Pipe Sutututu]

Did you rebuild the motor yourself?

Also silly question but did you clock the oil control rings properly? If not and say if all the ring gaps were all aligned you'll have this issue.

[drifter17a]

I did ‘t rebuild but with a tuner having 10 years of experience and many skyline seen there then I would have though all rings are clocked( not aligned) unless he has given it to one of his workers and they have f**ked up

 

re run in, he did and I wasn’t there . I got it back after car had run in excess of 5 hours and currently on 300 miles of the bed in oil

 

would you use baby oil for first start up?

[Ben C34]

6 minutes ago, drifter17a said:

would you use baby oil for first start up?

hmmmmmmm..

 

Need more info man. there are many reasons an engine can smoke, with different causes. But realistically you should be directing your questions and concerns should be directed to the builder.

 

[KiwiRS4T]

5 minutes ago, drifter17a said:

would you use baby oil for first start up?

You need to read more carefully. There is no mention of baby oil anywhere.

The run in procedure is important. I would want to be there.

To repeat a relevant question have you measured any oil consumption?

[drifter17a]

6 hours ago, KiwiRS4T said:

You need to read more carefully. There is no mention of baby oil anywhere.

The run in procedure is important. I would want to be there.

To repeat a relevant question have you measured any oil consumption?

oh was going to bed and red it as baby oil

 

nope but will check it today. It has an extended sump with 7 liter oil capacity buffled  custom made

[John iatrides]

Did he forget to install valve stems or did you reuse the olds ones?

[KiwiRS4T]

11 hours ago, John iatrides said:

Did he forget to install valve stems or did you reuse the olds ones?

Valves aren't much use without stems.

[John iatrides]

Yes, it will cause smoke if one got damaged or wasn't fitted properly.

[Ben C34]

26 minutes ago, John iatrides said:

Yes, it will cause smoke if one got damaged or wasn't fitted properly.

A valve without a stem isn't a valve, you are refering to valve stem seals, big difference!

[John iatrides]

Run a compression test to see what all your cylinder pressures are that will show if the rings seated. I'd call your tuner up and ask him who built your engine to c if they reused valve stems or maybe didn't install one correctly or tell your tuner what's going on he should have the best insight on the topic.

[GTSBoy]

1 hour ago, John iatrides said:

valve stem seals

Fixed that for you again. In case it didn't sink in the first time.