Blow by!!!

[Jason Porter]

OK, so an update on the 1911cc type 4 in my bug.

This morning, I'm leaving an exit ramp light at full throttle, when at about 5,000 RPMS in 2nd, I push in the clutch and shift to third.

As I'm shifting, I look in the rearview mirror, and I see a cloud of light greyish smoke.

As a test, I revved it to 4,500, and hit the brakes without pushing in the clutch. And VOILA! More oil smoke

So, since I'm at around 1,500 miles, it looks like a top end tear down, mild honing, and new rings.

WTF WTF WTF WTF WTF WTF WTF ...Sorry, just venting.

[SGB]

Sure it isn't just too rich? Done a compression test yet?

[Jason Porter]

It's definitely not to rich, and it's burning a little oil too.

[Scooter311]

Aw crap dude, I know how it feels - it's just a machine (a simple one at that), it can be fixed. At least it's fast!
How did you break it in and seat the rings? I shut mine down after less than 10 minutes cause of an oil leak, and I won't be starting it up again till the weekend now, and not actually driving it until after that.

[Jason Porter]

I didn't use non-detergent oil. That's pretty much the only thing I did wrong.

[wrongpew]

What's the issue with non-detergent oil during break-in? I thought short run times (15 min.) with cool-down periods and low engine speeds are critical for any air-cooled engine.

[Jason Porter]

Detergent oil cleans the cylinder walls, and make it a little slipperier (is that a word?), so sometimes the rings don't seat.

Obviously, the heat cycling and proper loading is the most important aspect of break-in, but oil choices can be critical also.

Ask most old VW guys, and they'll tell you to use non-detergent oil during the first 500-1000 miles.

[wrongpew]

I know this sounds crazy, but I've heard a bit of Bon Ami down the throat of a carbureted engine seats the rings right nice without collateral damage.

[Jared at Pelican Parts]

That was actually a dealer issued tech bulletin for Chevrolet in the 1950's when they came out with the 283 small block. It's not something I'd reccommend doing to ANY engine though...

[wrongpew]

That's an interesting fact and I'd have to agree against those meaures. I heard it from a drag racer which might explain the need for quick fixes. Speaking of rings, are there any chrome rings for the 914?

[jhadler]

Originally posted by wrongpew
That's an interesting fact and I'd have to agree against those meaures. I heard it from a drag racer which might explain the need for quick fixes. Speaking of rings, are there any chrome rings for the 914?

Probably, but chrome rings I think take forever to seat. The material is just that much harder than the soft iron conventional rings are made of. The one selling point of a chrome ring? They will last forever, just about as long as it takes to get them seated...

All IMHO of course...

-Josh2

[Jake Raby]

What pistons and rings did you use... If they were Grant rings or those Chinese pistons I know the issue..

You may have also smoked an intake valve guide.


We never have ring seating issues.. Its all in the hone patterns.. I use a plateau finish and it works fine.

[Jason Porter]

KB P/C's from European, with Hastings rings. Any ideas Jake?

[Jake Raby]

Damn.... What was your skirt clearances?? Did you run their cylinders also??

If so, they are tight and sometimes smoke a skirt, I bet thats what happened. The ONLY way to fly is bored German cylinders and you need .0023 clearance- they specify .0015 but its too tight

[Jason Porter]

I'll be re-honing and doing everything over this weekend. I'm not sure of my skirt clearances, I'll have to look in my notes. I remember it did seem tight.

Yes, I ran their cylinders. They'll be fine after me and my Bosch 3/8" drill get through wit' da' honin' baby.

[Bleyseng]

So Jake, Whats the issue with the Chinese pistons?
Geoff

[Scooter311]

Hey Jason
So will you need new rings as well after honing?
Remember, without this stuff life would be boring, and we'd all be collecting stamps, or golfing, or saving money.

Jeff

[Jason Porter]

Originally posted by Bleyseng
So Jake, Whats the issue with the Chinese pistons?
Geoff

FYI, all the following information is from a long phone conversation with Jake yesterday.

Basically, there isn't any quality control with these cylinders. Jakes cooked some, a very few given, but some of these pistons on his dyno. The cylinders are sometimes a thousandth too small on the ID, and they end up being to tight for Keith Black pistons.

The pistons them selves are fine. Keith Black makes a high quality product, and they are very stringent with quality control.

Originally posted by Scooter311
Hey Jason
So will you need new rings as well after honing?
Remember, without this stuff life would be boring, and we'd all be collecting stamps, or golfing, or saving money.

Jeff

I'm going to do a couple of tests today, to see which cylinder(s) are the problem. Then I'll replace those P/C(s) as necessary. New rings will of course go on new pistons.

After that, I'll bolt my new pro street gearbox, and go make a few new high performance German and Japanese cars angry and disappointed in the amountt of money they spent

[Jake Raby]

Chinese parts don't belong in a German engine...

[Bleyseng]

Well, that being said, WTF is wrong with them?


Geoff