Oil restrictors

[BracketNova]

What's eveyones opinions? My engine smokes when I start it pretty decent. I don't have valve seals and my rings are at 20% leakage. The machine shop I talked to said I needed to use oil restrictors...said I was flooding the top end with oil down the track and it was settling on my valves so when I start it...smoke.

Has anyone had this problem...was it fixed w/ oil restrictors?

396 BBC, iron heads, I have a solid cam and roller rockers.

[supernova]

I run them in mine.

But I drilled the .030 holes out to a .090 hole as to get a little more oil to the top. The .030 hole is too restrictive.

[sc racing]

Sounds like its time to freshen up the engine. Usually the intakes get a seal but the exhaust dont. Ive heard different opinions on the restrictors but drilling them out seems to be the thing to do if you do use them.Thats what I did when I had them.

[want-a-be]

I drill em to .090" and run the restrictors without the o-ring. I would rather run the valve seals then not. Built engines both ways. I don't have any problems at all when I run the seals.

Have you taken a good look at how the drain back holes are? I've seen them blocks a bit with a missalignment between the block and head. It's the lil' details that will bite you sometimes.

Don

[BracketNova]

Good to know, good to know. I'm trying to not have to freshen my motor , I would like to just leave it for the upcoming season, stack some cash and build a bigger one. I figured since the machine shop I talked to was shocked I didn't have restrictors I could drop my tranny and flexplate and give it a shot...without a whole lota' $$$ to try it.

[invegarating]

Hey Guys,

I have always used oil restrictors and (knock on wood) have never had as issue with them,when I ran a GM block I drilled them and removed o-rings,the Donovan block I have now has them permenantly installed.
My car gets between 100-150 miles per year with lots of idling and never a problem,plus the occasional trips to the track...I am still using the same 7 yr old crankshaft
I believe the benefits outweigh any disadvantages,and just as important as valve stem flooding is the returning oil creating windage in the crankcase which is eating up horsepower that has just been produced,I think that any form of windage control is benefitial.

[wikd69]

What is the advantage of building without valve seals ? Is this a coil bind / clearance issue ?

[BracketNova]

What is the advantage of building without valve seals ? Is this a coil bind / clearance issue ?

This just popped into my head...but don't they just come off the head and stay up on the top of the valve stem after awhile.

[wikd69]

What is the advantage of building without valve seals ? Is this a coil bind / clearance issue ?

This just popped into my head...but don't they just come off the head and stay up on the top of the valve stem after awhile.

I've not seen that - they typically have some sort of locking lip which snaps over a matching groove in the valve guide, protruding frin the head. This keeps the seals in place, usually.

[BracketNova]

Hm...I wonder if I should just try some valve seals first

[wikd69]

Hm...I wonder if I should just try some valve seals first

I'd give that a try - you can install the seals without pulling heads - try my patented rope in the sparkplug hole trick and get yer self a rocker stud mounted spring compressor.

[BracketNova]

Rope in the sparkplug hole...you'll have to enlighten me on that one. I was planning on using my leak down checker to keep the cylinder filled with air.

[sc racing]

stock type "umbrella" seals dont have a locking clip but the ones that do require the od of the guide to be machined down. The seal is supposed to wipe the oil (some of it) off the valve stem but it has to let a little in to lube the guide or you will seize a valve If your guides are worn seals may not help but I would put them on the intakes and see what happens I would never put restrictors in a flat tappet engine.

[wikd69]

Rope in the sparkplug hole...you'll have to enlighten me on that one. I was planning on using my leak down checker to keep the cylinder filled with air.

I heard about this trick and it worked slick. I gather compressed air works as well, but I could not see being able to leave the valves & keepers apart overnite using that method.

Pickup some 1/4" soft nylon rope and feed in into the sparkplug hole, filling the top of the cylinder. Roll the piston around to TDC and you're good. Here's a couple of pix.

[BracketNova]

Huh...woulda never thought of that