Pelican Parts
Parts Catalog Accessories Catalog How To Articles Tech Forums
Call Pelican Parts at 888-280-7799
Shopping Cart Cart | Project List | Order Status | Help



Go Back   Pelican Parts Forums > Porsche Forums > Porsche 924/944/968 Technical Forum


Reply
 
LinkBack Thread Tools Rate Thread
Author
Thread Post New Thread    Reply
Registered User
 
Eldorado's Avatar
 
Join Date: Apr 2005
Location: Ontario, Canada
Posts: 4,553
OT, but you guys know your stuff.. so....

hey guys, got an off topic question here for ya.. hope it's alright.. my girlfriend's dad owns a 79 thunderbird.. he's an original owner, and this thing is in showroom shape..

he hasn't been able to drive it at all this summer because it's got a running problem.

at first it wouldn't start. thought to be a carb problem, he got a new one.. installed it and tried to start it, no dice... he dumped some gas directly into the carb, and it would start beautifully and run as it should.. until the gas ran out.

the mechanical fuel pump is working just fine.. there's pressure in the line.. so if it's not that, what could it be? I thought it may be a blockage in the fuel line between the pump and carb somewhere, but I'm not too sure...

come on guys, dig through your car knowledge and lets see if i can score some points with her dad! lol

__________________
Kyle

2008 Mini Cooper // '83 Porsche 944 // '01 Mazda Protege [sold] //
"Never break more than you fix!" - SoCal Driver
Old 10-02-2006, 03:03 PM
  Pelican Parts Catalog | Tech Articles | Promos & Specials    Reply With Quote #1 (permalink)
Registered User
 
bearone2's Avatar
 
Join Date: Jun 2003
Location: Phoenix, AZ
Posts: 1,327
the gas might have gone bad/varnish and is plugging up everything.
__________________
87 951, K27/6, Almond Beige, 17" Turbotwist
87 944S, alpine white, 5sp died a violent death
84 944, silver/brown, auto, gone but not forgotten

"may the force be with you"
Old 10-02-2006, 03:46 PM
  Pelican Parts Catalog | Tech Articles | Promos & Specials    Reply With Quote #2 (permalink)
Registered User
 
Razorback1980's Avatar
 
Join Date: Nov 2005
Location: Houston, Texas
Posts: 2,944
Garage
Send a message via AIM to Razorback1980
You have proved it to be a fuel problem by dumping gas in the carburetor. Next you just have to start tracing the problem backward. You should be able to loosen the fuel line at the carburetor and put a hose on it running to a can on the floor..then turn the engine over. There will probably not be any gas there or not much. If there is, then sometimes they put a small filter in the carburetor. The way to tell is it will be right where the line you took loose is. If there is a bigger nut on the carburetor there, then remove it and look for a tiny usually brass looking filter there. If you do not have gas coming in big spurts out of the line, then take the line loose from the fuel pump and while cranking the starter see if gas is coming steadily out of the fuel pump. If not, then pull the gas line from the other side of the pump. Gas should run out of there at a steady rate without cranking. If it doesn't, then go to a parts store and see if you can get a small squeeze pump and try to pull the gas through the line. Not recommended but if you are foolish like me (and cheap) try to syphon the gas through the line....damn, that gas tastes good....for days! If not, then move on further back and see if there is a filter in the line somewhere. If no filter, then it's a problem in the tank. I'm sure you will have no problem finding the issue. A little more simple system than fuel injection. Gravity flow (for the most part to the pump on the engine) with a little help from the fuel pump and the pump moves it on up to the carburetor. The carburetor stops the flow of gasoline when it has enough there already. That's really all there is to it. Probably going to wind up being the fuel pump. They have a rubber diaphram inside that breaks over time...or plugged fuel filter.

Edit: I forgot to tell you that if you have fuel flow to the pump but not much going up to the carb, it's the fuel pump, but I'm guessing you knew that already.
__________________
Tom

1990 944S2 Cabriolet
2002 Chevy Silverado 2500HD
2003 Maroon Ford F350 dually

Last edited by Razorback1980; 10-02-2006 at 04:49 PM..
Old 10-02-2006, 04:36 PM
  Pelican Parts Catalog | Tech Articles | Promos & Specials    Reply With Quote #3 (permalink)
Registered User
 
Eldorado's Avatar
 
Join Date: Apr 2005
Location: Ontario, Canada
Posts: 4,553
thanks tom... pretty simple troubleshooting there...

i've never seen a mechanical fuel pump before.. it runs off of a belt joined to the cam.... probably common with older cars.. just never seen one!
__________________
Kyle

2008 Mini Cooper // '83 Porsche 944 // '01 Mazda Protege [sold] //
"Never break more than you fix!" - SoCal Driver
Old 10-02-2006, 05:42 PM
  Pelican Parts Catalog | Tech Articles | Promos & Specials    Reply With Quote #4 (permalink)
Registered User
 
Join Date: Apr 2003
Location: Durban,South Africa
Posts: 327
Garage
My late father in law was a different kind of guy. When the mechanical petrol pump packed in, saw him drive his 58 chev to a garage with a petrol can balanced on the car roof, which he held by hand, and a siphon tube running down to the carb. Just had to siphon the petrol to get the flow going before connecting to the carb. He liked to live on the edge a bit.
Old 10-03-2006, 12:14 AM
  Pelican Parts Catalog | Tech Articles | Promos & Specials    Reply With Quote #5 (permalink)
Registered User
 
Eldorado's Avatar
 
Join Date: Apr 2005
Location: Ontario, Canada
Posts: 4,553
Quote:
Originally posted by Paul Glasson
My late father in law was a different kind of guy. When the mechanical petrol pump packed in, saw him drive his 58 chev to a garage with a petrol can balanced on the car roof, which he held by hand, and a siphon tube running down to the carb. Just had to siphon the petrol to get the flow going before connecting to the carb. He liked to live on the edge a bit.
at least he always knew exactly how much gas he had!
__________________
Kyle

2008 Mini Cooper // '83 Porsche 944 // '01 Mazda Protege [sold] //
"Never break more than you fix!" - SoCal Driver
Old 10-03-2006, 05:00 AM
  Pelican Parts Catalog | Tech Articles | Promos & Specials    Reply With Quote #6 (permalink)
 
Registered User
 
Join Date: May 2004
Location: Brandon FL
Posts: 371
If it's been sitting for awhile, the gas has evaporated in the carburator and gummed up the float valve & jets. You might be able to remove the carb, and fill the fuel bowl a carburator cleaner to remove the varnish. If not, you will need to rebuild the carb.
__________________
Rick
99 996C4
06 525XI
87 944S - Sold
77 924 - Sold
Old 10-03-2006, 08:30 AM
  Pelican Parts Catalog | Tech Articles | Promos & Specials    Reply With Quote #7 (permalink)
Registered User
 
Eldorado's Avatar
 
Join Date: Apr 2005
Location: Ontario, Canada
Posts: 4,553
he put a whole new carb in.
__________________
Kyle

2008 Mini Cooper // '83 Porsche 944 // '01 Mazda Protege [sold] //
"Never break more than you fix!" - SoCal Driver
Old 10-03-2006, 09:00 AM
  Pelican Parts Catalog | Tech Articles | Promos & Specials    Reply With Quote #8 (permalink)
Registered User
 
Baza's Avatar
 
Join Date: Jan 2003
Location: Newcastle, Australia
Posts: 295
If its the fuel pump look at the option of replacing it with an electric pump.
__________________
Always start with the cheapest option first

83 NA Gaurds Red ( Home at last)
Holden/Opel Vectra 2002
Old 10-03-2006, 08:10 PM
  Pelican Parts Catalog | Tech Articles | Promos & Specials    Reply With Quote #9 (permalink)
Registered User
 
Eldorado's Avatar
 
Join Date: Apr 2005
Location: Ontario, Canada
Posts: 4,553
again, as stated.. the fuel pump is working just fine..
__________________
Kyle

2008 Mini Cooper // '83 Porsche 944 // '01 Mazda Protege [sold] //
"Never break more than you fix!" - SoCal Driver
Old 10-03-2006, 09:26 PM
  Pelican Parts Catalog | Tech Articles | Promos & Specials    Reply With Quote #10 (permalink)
Registered User
 
The Chris's Avatar
 
Join Date: Sep 2004
Location: MA
Posts: 186
I would start by replacing the fuel lines from the pump to the carb
__________________
2008 BMW M3 | 6spd | Dinan catback
Old 10-04-2006, 07:18 AM
  Pelican Parts Catalog | Tech Articles | Promos & Specials    Reply With Quote #11 (permalink)
Registered User
 
Join Date: Dec 2005
Posts: 673
sounds like the needle and seat are stuck together or plugged try tapping on the carb where the fuel line attaches.

This would be a rare coincidence considering you are workingwith 2 different carbs. Are you sure the Fuel pump is working? If the car runs fine by filling the float bowl and your sure the fuel pump is working then the ONLY Thingit can be is the needle and seat (valve that opens and closes as the float rises) It is possible that the hose between the Fuel
pmp and carb is detirating and parts of the rubber are plugging the fuel entrance

__________________
Sid
splitting my obsessions with a crow bar.
87 DD Black 951 Holset HX40-35 custom garrett turbine, Ford MAF, Rogue tuned,SLM stroker, best ET 11.4..best mph 127
Old 10-06-2006, 06:33 AM
  Pelican Parts Catalog | Tech Articles | Promos & Specials    Reply With Quote #12 (permalink)
Reply

Thread Tools
Rate This Thread
Rate This Thread:

 


All times are GMT -8. The time now is 04:34 PM.


 
Powered by vBulletin® Version 3.8.7
Copyright ©2000 - 2020, vBulletin Solutions, Inc.
Search Engine Optimization by vBSEO 3.6.0
Copyright 2020 Pelican Parts, LLC - Posts may be archived for display on the Pelican Parts Website -    DMCA Registered Agent Contact Page
 

DTO Garage Plus vBulletin Plugins by Drive Thru Online, Inc.