Notices
928 Forum 1978-1995
Sponsored by:
Sponsored by: 928 Specialists

OB fuel injection question

Thread Tools
 
Search this Thread
 
Old Dec 11, 2007 | 04:02 AM
  #1  
6mil928's Avatar
6mil928
Thread Starter
Race Car
 
Joined: Sep 2007
Posts: 3,663
Likes: 1
From: No where Oklahoma AKA "The Dust Bowl" In The Arm pit Of Hell
Default OB fuel injection question

Well guys it's been cold and icy here for the last few days. Driving home in my 81 OB tonight I was almost home and I started smelling gas. I thought it was just in the air until I got out and it was very strong around my car. I popped the hood and found one of the short rubber hoses that feed my fuel injectors from the fuel rail leaking. I looked at them before the 3rd coast and they were very hard and needed to be changed according to Russ. Well I guess he was right so here's my question. Is there anything special to changing these hoses? Do I just lift the fuel rail up and remove and replace the little hose sections? I've been told that it needs to be fuel injection hose. Does that sound correct? Does anyone know of a tutorial on doing this job? Thanks for the help guys you are the best Jason
Reply
Old Dec 11, 2007 | 04:43 PM
  #2  
jpitman2's Avatar
jpitman2
Rennlist Member
 
Joined: Dec 2002
Posts: 5,283
Likes: 52
From: Australia
Default

An OB with L-jet? yes the hoses need to be suitable for Injection pressures (~40psi), and I am sure somebody who has done it will chime in. Clips that wont cut into the hose are worth looking for.
jp 83 Euro S AT 51k
Reply
Old Dec 11, 2007 | 04:49 PM
  #3  
Airflite40's Avatar
Airflite40
Official Rennlist
Borat Impersonator
Rennlist Member
20 Year Member
 
Joined: Sep 2003
Posts: 5,018
Likes: 37
From: St Augustine, FL
Default

I would say you just dodged a bullet there!! glad your car is not in a ball of flames!
Reply
Old Dec 11, 2007 | 04:53 PM
  #4  
bernard farquart's Avatar
bernard farquart
Drifting
20 Year Member
 
Joined: Feb 2005
Posts: 2,932
Likes: 1
From: Seattle, where everyone is above average, and the women are all beautiful
Default

If you have the same set up as I do, that is L-jet, then I have found it easier to just pull all four out with the fuel rail, put new o-rings on (like 5 bux for a side) and re-do the whole thing at once, on the bench. you do want to get the proper fuel injection rated hose, and the proper fuel injection hose clamps, very common parts at any local parts store. Pretty easy job, some have said that the lower o-rings stuck, I did not have that problem, but I only have 205K miles, so mine may have still been factory fresh.
Reply
Old Dec 11, 2007 | 05:31 PM
  #5  
6mil928's Avatar
6mil928
Thread Starter
Race Car
 
Joined: Sep 2007
Posts: 3,663
Likes: 1
From: No where Oklahoma AKA "The Dust Bowl" In The Arm pit Of Hell
Default

Originally Posted by jpitman2
An OB with L-jet? yes the hoses need to be suitable for Injection pressures (~40psi), and I am sure somebody who has done it will chime in. Clips that wont cut into the hose are worth looking for.
jp 83 Euro S AT 51k

Yes it's L-jet according to Russ. Looking at it last night I don't recall seeing clips on the hoses. Do they look like hose clamps or something else? Jason
Reply
Old Dec 11, 2007 | 05:33 PM
  #6  
6mil928's Avatar
6mil928
Thread Starter
Race Car
 
Joined: Sep 2007
Posts: 3,663
Likes: 1
From: No where Oklahoma AKA "The Dust Bowl" In The Arm pit Of Hell
Default

Originally Posted by Airflite40
I would say you just dodged a bullet there!! glad your car is not in a ball of flames!
Your definately right!! Thank god for a short drive to work. I've still been doing other things to the car and hadn't got to the hoses yet. Jason
Reply
Old Dec 11, 2007 | 05:34 PM
  #7  
6mil928's Avatar
6mil928
Thread Starter
Race Car
 
Joined: Sep 2007
Posts: 3,663
Likes: 1
From: No where Oklahoma AKA "The Dust Bowl" In The Arm pit Of Hell
Default

Originally Posted by bernard farquart
If you have the same set up as I do, that is L-jet, then I have found it easier to just pull all four out with the fuel rail, put new o-rings on (like 5 bux for a side) and re-do the whole thing at once, on the bench. you do want to get the proper fuel injection rated hose, and the proper fuel injection hose clamps, very common parts at any local parts store. Pretty easy job, some have said that the lower o-rings stuck, I did not have that problem, but I only have 205K miles, so mine may have still been factory fresh.
Thanks for the advice sounds like a plan. 205K my car feels so young now with 94K But I'm sure my neglected Ebay car is in much worse shape despite the low miles. Jason
Reply
Old Dec 11, 2007 | 06:41 PM
  #8  
kjurkic's Avatar
kjurkic
Instructor
 
Joined: Feb 2007
Posts: 238
Likes: 0
From: Da Island, mon! (VI,BC,CA)
Default short inj hoses

Some will argue different, but in my experience, you don't need clamps, the rail & the injector are barbed, and what LOOK like compression rings are just decorative. When I did my '80 last spring, I had to grind off the metal "compression rings", then use a wire wheel to abrade the remains of the hoses off of the barbs. Standard injection rated line is fine ~5/16" IIRC. Pull injector rails & injectors together & replace all really is best/easiest.

You should consider replacing the feed & return hoses on the pass. side as well, since they are likely the same age. They are pricey, and a total b14tch to remove if original & untouched.

WYAIT....vac hoses, coolant hoses, oil/intake hoses, heater hoses.....................>>>>>>>>>>

Ken
Reply
Old Dec 11, 2007 | 06:42 PM
  #9  
hacker-pschorr's Avatar
hacker-pschorr
Administrator
20 Year Member
 
Joined: Aug 2001
Posts: 27,394
Likes: 3,036
From: Up Nort
Default

I've done this a few times now. The factory holders for the fuel hose it a bitch to remove. I use a small hack saw to cut away the small bowl shape holder on each end.

There are two seals on each injector - replace all of those (one of each of these per injector:
http://www.mailordercentral.com/928i...0133%20261%20A
http://www.mailordercentral.com/928i...11%20133%20263

928 International also sells this kit:
http://www.mailordercentral.com/928i...110%20903%2000

The only part I do not like about this kit is the use of the bowl shaped hose holder. The clamps in that picture (norma band clamps) I use 16 of those, one on each end of the hose versus using the types of clamps the factory uses.

Since you are taking off the rails anyway - replace the two short hose pieces going to the fuel pressure regulators. Same type of hose, same age as the one leaking on your injector.
Reply
Old Dec 11, 2007 | 09:32 PM
  #10  
ROG100's Avatar
ROG100
Basic Sponsor
Rennlist
Site Sponsor

20 Year Member
 
Joined: Jan 2003
Posts: 16,942
Likes: 1,045
From: Double Oak, TX
Default

Jason,
I have all the hose and clamps and seals you will need for a lot less money.
Other than that do as Erik says.
Roger
__________________

Does it have the "Do It Yourself" manual transmission, or the superior "Fully Equipped by Porsche" Automatic Transmission? George Layton March 2014

928 Owners are ".....a secret sect of quietly assured Porsche pragmatists who in near anonymity appreciate the prodigious, easy going prowess of the 928."






Reply
Old Dec 12, 2007 | 12:03 AM
  #11  
6mil928's Avatar
6mil928
Thread Starter
Race Car
 
Joined: Sep 2007
Posts: 3,663
Likes: 1
From: No where Oklahoma AKA "The Dust Bowl" In The Arm pit Of Hell
Default

Originally Posted by kjurkic
Some will argue different, but in my experience, you don't need clamps, the rail & the injector are barbed, and what LOOK like compression rings are just decorative. When I did my '80 last spring, I had to grind off the metal "compression rings", then use a wire wheel to abrade the remains of the hoses off of the barbs. Standard injection rated line is fine ~5/16" IIRC. Pull injector rails & injectors together & replace all really is best/easiest.

You should consider replacing the feed & return hoses on the pass. side as well, since they are likely the same age. They are pricey, and a total b14tch to remove if original & untouched.

WYAIT....vac hoses, coolant hoses, oil/intake hoses, heater hoses.....................>>>>>>>>>>

Ken

I'll definately change everything hose related on the motor while I'm at it. I'm with you everything is pretty well toast if it's original like the fuel injection hoses. Jason
Reply
Old Dec 12, 2007 | 12:06 AM
  #12  
6mil928's Avatar
6mil928
Thread Starter
Race Car
 
Joined: Sep 2007
Posts: 3,663
Likes: 1
From: No where Oklahoma AKA "The Dust Bowl" In The Arm pit Of Hell
Default

Originally Posted by ROG100
Jason,
I have all the hose and clamps and seals you will need for a lot less money.
Other than that do as Erik says.
Roger
Thanks Roger I'll PM you. Jason
Reply
Old Dec 12, 2007 | 12:08 AM
  #13  
6mil928's Avatar
6mil928
Thread Starter
Race Car
 
Joined: Sep 2007
Posts: 3,663
Likes: 1
From: No where Oklahoma AKA "The Dust Bowl" In The Arm pit Of Hell
Default

Originally Posted by kjurkic
Some will argue different, but in my experience, you don't need clamps, the rail & the injector are barbed, and what LOOK like compression rings are just decorative. When I did my '80 last spring, I had to grind off the metal "compression rings", then use a wire wheel to abrade the remains of the hoses off of the barbs. Standard injection rated line is fine ~5/16" IIRC. Pull injector rails & injectors together & replace all really is best/easiest.

You should consider replacing the feed & return hoses on the pass. side as well, since they are likely the same age. They are pricey, and a total b14tch to remove if original & untouched.

WYAIT....vac hoses, coolant hoses, oil/intake hoses, heater hoses.....................>>>>>>>>>>

Ken
How do the bowl shaped compression rings that are on both sides of the hose work? Jason
Reply
Old Dec 12, 2007 | 03:57 AM
  #14  
6mil928's Avatar
6mil928
Thread Starter
Race Car
 
Joined: Sep 2007
Posts: 3,663
Likes: 1
From: No where Oklahoma AKA "The Dust Bowl" In The Arm pit Of Hell
Default

Would you guys say this is a long job to complete as far as just doing the fuel rail hoses? Jason
Reply
Old Dec 12, 2007 | 04:45 PM
  #15  
kjurkic's Avatar
kjurkic
Instructor
 
Joined: Feb 2007
Posts: 238
Likes: 0
From: Da Island, mon! (VI,BC,CA)
Default

Just the injector hoses should take no more than a couple of hours for an (non-928) experienced DIY'er, less than 1 hour for those with 928/prior experience.

YMMV
Ken
more info here in my old post:
https://rennlist.com/forums/928-forum/349586-1980-intake-r-and-r-lotta-work-but-success.html

Last edited by kjurkic; Dec 12, 2007 at 04:58 PM. Reason: link added
Reply



All times are GMT -3. The time now is 08:22 PM.