Change font size
It is currently Thu Mar 28, 2024 8:48 am


Post a new topicPost a reply Page 1 of 1   [ 8 posts ]
Author Message
 Post subject: B18 compression
PostPosted: Wed Apr 16, 2014 2:13 pm 
Whost Pore

Joined: Sun Feb 11, 2007 7:26 pm
Posts: 558
Location: E-Town
Well, at the end of the season last year I was coming up a hill with a little bit of spirit heard a bit of a whizzing sound and saw a nice blue plume of smoke behind me. car was running rough but still running, had oil, etc.
Limped it the 2 miles or so home....

had a chance to check compression today (Fired right up after siting all winter!) and i'm at 0-110-120-120
squirted some oil in, no change, but that really doesn't mean much...

Sounds like the head has to come off.

Any guesses?
Any good step-by-steps on pulling a b18 head?
I'm hoping it's just a valve issue....


Top
 Profile  
 
 Post subject: Re: B18 compression
PostPosted: Thu Apr 17, 2014 12:06 pm 
Haha, I just built a W24 Octo-Turbo, now what?!
User avatar

Joined: Wed Jun 14, 2006 4:19 pm
Posts: 3131
Location: Lethbridge, AB
No pressure at all...that's odd. Any other signs (pressurized crankcase or cooling system?). Could be a valve finally bit the dust. When I read the first line, I thought it may be you wiped a lobe of the cam - but zero compression is either a holed piston or a burnt valve.

Pulling the head is simply a matter of removing the rocker shaft assembly and releasing the 10 head bolts (coolant lines etc of course). Easy peasy.

_________________
Coburn Performance - OCD comes naturally.


Top
 Profile  
 
 Post subject: Re: B18 compression
PostPosted: Thu Apr 17, 2014 1:05 pm 
Whost Pore

Joined: Sun Feb 11, 2007 7:26 pm
Posts: 558
Location: E-Town
Pretty darn simple, had a bit of trouble figuring out the heat shield on the carbs... but i'm rusty after not wrenching all winter...


Unfortunately........
Image
Anyone got any ideas what would be the cause of something like this?
I had a few times it got a touch warm, but definitely never went crazy overheated on it.
Always had at least 20lbs of oil pressure, (Ran 15-40 diesel oil in it for a while because of the zinc)

Looks like i'm in need of a new short block.


Top
 Profile  
 
 Post subject: Re: B18 compression
PostPosted: Thu Apr 17, 2014 7:49 pm 
Haha, I just built a W24 Octo-Turbo, now what?!
User avatar

Joined: Wed Jun 14, 2006 4:19 pm
Posts: 3131
Location: Lethbridge, AB
what's with the crown of that piston…looks melted. That missing piece could be due to detonation. I've got a couple of sets of used pistons with some life if you're interested.

_________________
Coburn Performance - OCD comes naturally.


Top
 Profile  
 
 Post subject: Re: B18 compression
PostPosted: Thu Apr 17, 2014 8:59 pm 
Whost Pore

Joined: Sun Feb 11, 2007 7:26 pm
Posts: 558
Location: E-Town
carbon build up... pretty nasty... other cylinders are much cleaner. I assume it's from the oil that would have got in there and burnt up. there's a nick in the cylinder wall so not sure if it's a complete rebuild or an easy fix. I've gotta see how bad it is. Carb tune was fairly decent, plugs all read good too.

I'll bring home some indicators and measure it out tuesday.


Top
 Profile  
 
 Post subject: Re: B18 compression
PostPosted: Fri Apr 18, 2014 10:35 am 
Haha, I just built a W24 Octo-Turbo, now what?!
User avatar

Joined: Wed Jun 14, 2006 4:19 pm
Posts: 3131
Location: Lethbridge, AB
I just checked my used piston stock…I have a set of stock sized B18's and an odd-ball set of B20's (24 mm wrist pins…not worth it).

_________________
Coburn Performance - OCD comes naturally.


Top
 Profile  
 
 Post subject: Re: B18 compression
PostPosted: Mon Apr 21, 2014 4:29 pm 
Whost Pore

Joined: Sun Feb 11, 2007 7:26 pm
Posts: 558
Location: E-Town
Annnd there's no way I'll get away without boring this one out.
cylinder is quite out of round (0.028) and the part that was gouged is pretty deep (at least 0.080)

Options:
There's an A125 (b21) in a boat nearby, but i'd have to tear apart and get rid of the boat to get it... the 260 outdrive might be worth something though...

There's a 1995 VW AAD 1.9 TD (Mechanical injected) available for pretty cheap, eye-balling it, it would appear to clear the steering column... I can get an AZ6 transmission for cheap (6 speed from IS200/RX8/etc) and fit it with a toyota bellhousing adapter. The trans looks like it will clear the tranny tunnel of the PV... With the 4.10 gears and all this would put it into around 2800rpm at 105km/h, about what it was in the VW (closer to 3k if i remember right)

I could source another b18 or b20, but would probably be looking at 600-800 minimum by the time it's here. Plus any work to refurb. The diesel and trans could be had under 1k, figure another 2k for adapters/bits it's still a reasonable option.

I'm looking for a cruiser and not a go-fast car.


Top
 Profile  
 
 Post subject: Re: B18 compression
PostPosted: Tue Apr 22, 2014 10:00 am 
Vmax 200mph w00t!
User avatar

Joined: Mon Apr 19, 2010 4:21 pm
Posts: 265
Location: Saskatoon, Sk
here we go again :roll:

_________________
94' 944t "The Good One"
87' 780 5.0L V8


Top
 Profile  
 
Display posts from previous:  Sort by  
Post a new topicPost a reply Page 1 of 1   [ 8 posts ]


Who is online

Users browsing this forum: No registered users and 19 guests


You cannot post new topics in this forum
You cannot reply to topics in this forum
You cannot edit your posts in this forum
You cannot delete your posts in this forum
You cannot post attachments in this forum

Jump to:  
cron


Powered by phpBB © 2000, 2002, 2005, 2007 phpBB Group
610nm Style by Daniel St. Jules of Gamexe.net