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Engine Specific Info and Questions => IDI Engine => Topic started by: fc steve on November 03, 2009, 01:14:43 pm

Title: Ugh New engine time?
Post by: fc steve on November 03, 2009, 01:14:43 pm
car is an 81 rabbit with a 1.6 na motor in it.

   Just got a new set of injectors in it and its been starting and running great since i have installed them. But ive got a couple issues still. One that its had for a while is a fair amount of blowby. If i look at the hose and have it off of the intake i can see it puffing pretty hard. Seems to be in time with the engine on a particular cylinder. Is the head gasket leaking to an oil drain in the head possibly? I can see that the head gasket is leaking oil out of the front of the head in the normal spot.
    On to the big issue. I appear to be making oil :( the fuel doesnt really smell like diesel but in the past couple hundred miles the level has gone up on the stick about 3mm. (normally im adding a quart every 3-400 with the blowby and leaks i have) Is it possible that this is headgasket blowby related? Or does it sound like i have a hole going out?
    As i stated before the engine starts great once the plugs warm up Idles pretty smooth and seems top pull fine for a 50 hp car. Thank you guys in advance for your help.
Steven
Title: Re: Ugh New engine time?
Post by: Black Smokin' Diesel on November 03, 2009, 01:21:35 pm
Looks like you have two issues here. One being a bad headgasket seeing that it leaks on the front of the engine and second, worn piston rings. Blow-by and the oil level going UP are from worn rings. You should smell the oil for diesel in it. A compression and leak down test will tell you what's going on.
Title: Re: Ugh New engine time?
Post by: fc steve on November 03, 2009, 01:29:15 pm
Yeah time to buy a comp tester...


Like i said the oil doesnt really smell like fuel. But i am aware thats the reason that im "making" oil Anyone got a low mile motor for sale?
Title: Re: Ugh New engine time?
Post by: fc steve on November 03, 2009, 04:21:40 pm
What kind of luck have people had with re ringing these provided the bores are still in spec?
Title: Re: Ugh New engine time?
Post by: fc steve on November 03, 2009, 05:35:21 pm
Also i know its not likely but could a blown hg cause the making oil?
Title: Re: Ugh New engine time?
Post by: maxfax on November 03, 2009, 06:04:55 pm
How many maile do you have on it??

I as well as alot of others have had good luck with re ringing as long as the cylinders are decent..  I threw rings at one with about .003" wear in the cylinders and it was fine..   Just make sure you use decent quality rings, and hone the cylinders well..  

I'm not going to say it's inpossible for a HG to be making oil, but it's not real likely inless you have coolant going into the oil..    Since you would have the head off to do the gasket that woudl be the time to throw some rings in there as well...

One other note, (geting up to my podium) since you have a 1981 you car used the dreaded 11mm head bolts..
Read this:http://www.vwdiesel.net/forum/index.php?topic=21948.0 (http://www.vwdiesel.net/forum/index.php?topic=21948.0)
Title: Re: Ugh New engine time?
Post by: fc steve on November 03, 2009, 06:45:22 pm
Yeah previous owner installed arp studs. And its not coolant in the oil its not milky at all. Im looking at another 1.6 tomorrow. If it sounds good ill swap it and start to rebuild what is in there now.
Title: Re: Ugh New engine time?
Post by: maxfax on November 03, 2009, 06:54:37 pm
Thank your previous owner!!   Otherwise I'd say you're woes is all ring related..  Good luck on the other engine!

Let us know how the bores look on your current engine..   I've been surprised how little the bores wear on these on gennerally.. The engine I referred to earlier head a tad over 500K miles on it.. On the other end of the spectrum the one I am rebuilding for my car had terrible wear...  It was an old fart car, 177K miles but all short trips..  The bores were horrible....
Title: Re: Ugh New engine time?
Post by: fc steve on November 03, 2009, 10:01:17 pm
This thing only has 140k on it :/ Im gonna comp test the current engine before i pull it tomorrow. If they all test good i don't know what im gonna do different tho... It starts and runs fine. And the making oil is a classic ring deal :(
Title: Re: Ugh New engine time?
Post by: maxfax on November 03, 2009, 10:29:01 pm
Has your car ever had veg oil run though it that you know of??   Or did the po happen to replace rings?  Some brands of rings tend to suck big time....
Title: Re: Ugh New engine time?
Post by: fc steve on November 04, 2009, 09:11:31 am
   No veg oil from po he bought it from an old lady. And he didnt touch the bottom end. Gonna start pulling the head in a few.
Title: Re: Ugh New engine time?
Post by: fc steve on November 04, 2009, 12:22:59 pm
Head is off. No crosshatch left on bores but no scoring. #2 has some slight pitting about 2/3 down the bore. #3 exhaust port has HEAVY (1/8 in) wall of carbon all the way around.

The piston to wall clearance is around .012" stock spec is .0012" dunno if a re ring would do much good with bores that worn.
Title: Re: Ugh New engine time?
Post by: maxfax on November 04, 2009, 01:08:48 pm
Ooooh, you you may be pushing it there....   Sounds like another casulty of not being run enough...
Title: Re: Ugh New engine time?
Post by: fc steve on November 04, 2009, 06:43:30 pm
Yep ordering .5mm over pistons and bearings. rebuild time. How big can the cracks in the head get before i should worry?
Title: Re: Ugh New engine time?
Post by: rabbitman on November 04, 2009, 06:49:55 pm
Yep ordering .5mm over pistons and bearings. rebuild time. How big can the cracks in the head get before i should worry?

The bentley says the cracks between the valves can be no bigger than 2mm(?)
Title: Re: Ugh New engine time?
Post by: fc steve on November 09, 2009, 11:06:51 am
Got it all apart ready to go to the machine shop. On teardown i noticed that the intermediate shaft was pretty tight. The crank was much easier to turn than it was. So im gonna get new bearings installed and hope that fixes it. If not ill have to find a new shaft.

Anyone herd of that before?
Title: Re: Ugh New engine time?
Post by: truckinwagen on November 09, 2009, 01:12:46 pm
the motor I just pulled apart to rebuild had a very tight IM shaft, tight enough that it would not go back in without a mallet.

I am hoping that new bearings fixes it too.

-Owen
Title: Re: Ugh New engine time?
Post by: Black Smokin' Diesel on November 09, 2009, 05:11:48 pm
Yep ordering .5mm over pistons and bearings. rebuild time. How big can the cracks in the head get before i should worry?

The bentley says the cracks between the valves can be no bigger than 2mm(?)

It's actually 0.5 mm (.02 in.). 2mm in HUGE!!!
Title: Re: Ugh New engine time?
Post by: rabbitman on November 09, 2009, 08:14:24 pm
Yep ordering .5mm over pistons and bearings. rebuild time. How big can the cracks in the head get before i should worry?

The bentley says the cracks between the valves can be no bigger than 2mm(?)

It's actually 0.5 mm (.02 in.). 2mm in HUGE!!!

My mistake....I should've known better than to go by memory ::)
Title: Re: Ugh New engine time?
Post by: fc steve on November 10, 2009, 12:27:31 pm
Lol thanks for the clarification.
Title: Re: Ugh New engine time?
Post by: fc steve on November 19, 2009, 06:04:26 pm
Got the block back from the machinist today looks good. The new i shaft bearings fixed it right up turns nice and free now. Took the head apart inspected everything and lapped the valves.

Starting on bottom end assembly tomorrow.