ShopTalk Forums | Aircooled VW Tech & Restoration Help

Posted: **Tue Aug 11, 2020 10:58 am**

buguy wrote: ↑Tue Aug 11, 2020 10:46 am Could always full the chambers with something and see if anything leaks through.

Yeah, that was what I did first thing to see if the valves old compression. No leaks at all actually.

Posted: **Tue Aug 11, 2020 11:41 am**

out of curiosity what oil u using?

Posted: **Tue Aug 11, 2020 1:00 pm**

madmike wrote: ↑Tue Aug 11, 2020 11:41 am out of curiosity what oil u using?

Mobil 1 10w-30 full syn with a zddp additive. I have a pump-filter on there too.

Posted: **Tue Aug 11, 2020 6:25 pm**

After a bit of investigating I've found that my oil cooler was functioning properly. No restrictions. I did, however, find that when I did my Hoover mods I didnt grind the adjuster end of my rockers enough to allow a strong spray of oil to hit the back of my elephant foot adjusters. Also, as is typical with these heads, the cooling passages between the fins needed a bit more work than I put in when I got them.

If I had a way of measuring the valve to guide clearance on the stuck valve, I would. But I dont.

Posted: **Tue Aug 11, 2020 7:34 pm**

How does the valve feel in the guide? Have you had the spring off and done a little wiggle test? I don't have a way to measure either, but maybe you could get an idea by feel?
If it doesn't leak, i personally would run it. As long as it's not super floppy in the guide of course (which i doubt it is or it wouldn't have stuck).

Posted: **Fri Aug 14, 2020 9:12 pm**

Huh. Weirdest thing. I found that the head held water alright but I just bolted it in and it seems to be leaking now.

I haven't run it yet. Just turning it by hand and I can hear it hiss past the exhaust valve.

Ah well. I'll see if I cant try to run it tomorrow. I had to re-ring #2 and it needs to get broken in anyway. If it fails... I have a baja and it's no big thing to tear it down again.

Posted: **Sat Aug 15, 2020 3:51 am**

I hear ya on , easy to work on ,luv my removable apron & fenders , take all of 30 seconds to remove all mine ,,

Posted: **Sat Aug 15, 2020 3:59 am**

The exhaust valve could have been opening when you were turning it by hand. I'd run it and see what you've got. Maybe in the winter send the heads back to Roy for a refresh?

Posted: **Sat Aug 15, 2020 11:53 am**

Well it started up on all 4 cylinders. We'll see how well the new rings settle in. Right at the moment I can feel the pulses through the breather for sure.

Posted: **Sat Aug 15, 2020 12:15 pm**

You have a turbo. Putting a load on them and getting them seated should be no problem.

Posted: **Sat Aug 15, 2020 12:56 pm**

Excessive blowby is a sure sign of detonation issues.
I wouldn't doubt with that much head damage you could have easily cracked your pistons too.
Cracked pistons will come apart at some point......when is the question.
I've had blowby on my first set of P/C's and replaced them.
I replaced the second set when I had a severe case of detonation showing off and not lifting....not long before I was going on a 3500 mile trip to California......I replaced them to make sure I didn't have an issue a 1000 miles from home.

I saw CorysVdub pictures of the carnage when his piston let go......you can probably do a search and find them if you want.......it was ugly and the case and everything else was destroyed.

Posted: **Sat Aug 15, 2020 2:15 pm**

Clonebug wrote: ↑Sat Aug 15, 2020 12:56 pm Excessive blowby is a sure sign of detonation issues.
I wouldn't doubt with that much head damage you could have easily cracked your pistons too.
Cracked pistons will come apart at some point......when is the question.
I've had blowby on my first set of P/C's and replaced them.
I replaced the second set when I had a severe case of detonation showing off and not lifting....not long before I was going on a 3500 mile trip to California......I replaced them to make sure I didn't have an issue a 1000 miles from home.

I saw CorysVdub pictures of the carnage when his piston let go......you can probably do a search and find them if you want.......it was ugly and the case and everything else was destroyed.

Oh been there done that! I have the piston on the shelf reminding me of what can go wrong.

I had a spare matching piston on the shelf and replaced the piston and rings. I didnt, however, replace the cylinder. I honed the cylinder but I dont have torque plates and I used a flex hone with 3 stones.

Yeah, not the best way, but the worst that happens is I have to pull it apart again when/if the rings dont seal up.

Posted: **Sun Aug 16, 2020 4:18 am**

I call Kona out in Utah I think $135 for a set of AA cylinders to my door

that's cheap if u ask me

Posted: **Mon Aug 17, 2020 1:10 pm**

madmike wrote: ↑Sun Aug 16, 2020 4:18 am I call Kona out in Utah I think $135 for a set of AA cylinders to my door that's cheap if u ask me

John at Aircooled.net has single AA piston and cylinder sets for a measly 60 bucks or something. Since I only hurt a single cylinder, that's what I'll do of the rings dont fully seat.

So far so good though. I beat on the car offroad for a bit and now the car idles nice and smooth even at 600rpm. It sounds better at 900 though. I get light puffing from the breather at idle.

The boost gods gave me a slap on the wrist and I damn well better heed the warning! No more freeway time until the water-meth is installed.

And yes, I moved the O2 sensor to the correct position

Posted: **Mon Aug 17, 2020 1:31 pm**

are u gonna balance the pistons?

ShopTalk Forums | Aircooled VW Tech & Restoration Help

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