S1 fuel pump with integral non return valve
Discussion
to keep up the running commentary; I listened for the pump when switching the ignition on. Nothing. "Aha!" I thought, "maybe those PH experts are on to something." Cranking the engine resulted in no start as expected.
I then cracked open the filter outlet to check for fuel pressure. Sure enough, a fine spray vovered me and the engine bay.
Clean up and in frustration I turned the ignition again. Car starts first time and ticks over beautifully! I've fixed it!!
Turn engine off, and just to check my success I try to start it again. Nothing.
I then cracked open the filter outlet to check for fuel pressure. Sure enough, a fine spray vovered me and the engine bay.
Clean up and in frustration I turned the ignition again. Car starts first time and ticks over beautifully! I've fixed it!!
Turn engine off, and just to check my success I try to start it again. Nothing.
Puzzled for the moment why releasing the fuel pressure downstream of the pump might cause a K Jetronic to work. Immediate reaction is the fuel is OK, it is an intermittent electrical fault.
The place to test is the 7th injector, blue connector, side of the plenum chamber. With the electrics disconnected this should fire a fine mist and prove there is pressure downstream of the mechanical fuel distributor.
If yes then electrics are far more likely. Do you have access to a strobe light? If so connect it and see if you are getting a spark with all the plugs in.
Wild thought, these wont fire if the mixture is significantly out, there is no automatic compensation. I dont suppose enough fuel got into the air filter to richen the mixture for a period? The filter is right under the fuel filter.
Please tell me you haven't adjusted the mixture screw on the top of the mechanical fuel distributor!Please!!
The place to test is the 7th injector, blue connector, side of the plenum chamber. With the electrics disconnected this should fire a fine mist and prove there is pressure downstream of the mechanical fuel distributor.
If yes then electrics are far more likely. Do you have access to a strobe light? If so connect it and see if you are getting a spark with all the plugs in.
Wild thought, these wont fire if the mixture is significantly out, there is no automatic compensation. I dont suppose enough fuel got into the air filter to richen the mixture for a period? The filter is right under the fuel filter.
Please tell me you haven't adjusted the mixture screw on the top of the mechanical fuel distributor!Please!!
No. I haven't ahdjusted the mixture! My thinking is that something that was working isn't working now; it isn't an out of adjustment thing.
I'm glad someone else is puzzled by the random start. It certainly got me thinking about electrical problems again.
However I did take the opportunity (while Mrs Mungral was getting ready to go out) to check the airflow sensor. Other than it being covered in 29 years of grime (I was surprised it wasn't spotless) it moved smoothly and returned to closed.
There are some volts of electrical magic at the start valve but I'll take it out and check there's a fuel spray.
After that I'll be back to the ignition circuit. I did notice the coil was warm after cranking. Is this normal?
I'm glad someone else is puzzled by the random start. It certainly got me thinking about electrical problems again.
However I did take the opportunity (while Mrs Mungral was getting ready to go out) to check the airflow sensor. Other than it being covered in 29 years of grime (I was surprised it wasn't spotless) it moved smoothly and returned to closed.
There are some volts of electrical magic at the start valve but I'll take it out and check there's a fuel spray.
After that I'll be back to the ignition circuit. I did notice the coil was warm after cranking. Is this normal?
Hi, interesting cars these TVR's and the 2.8 is most interesting of all. For 'interesting' you may wish to substitute something else!!
You should hear the fuel pump click...but only if the fuel pressure has dropped a little. If the fuel accumulator and non return valave on the pump are working well the pressure will hold for some time and the pump wont need to work until here is a demand. 'Some time' is very difficult to define, some days on a very good car, quite a few hours on mine.
The coil will warm up but to get quite warm under cranking only doesnt sound right to me.
If your meter suggests a good circuit to the coil, breaking as it should, and a missing, weak or irregular spark on the strobe then get that coil changed, it isnt particularly expensive. If your is still mounted on the side of the plenum chamber I would recommend moving it to the grp firewall. It doesnt need the plenum to earth to and in the 2.8 that area isnt as well cooled as it is in the Granada so the coils can get unduly warm.
Still cant work out how it ran when you leaked petrol but doesnt now, unless it temporarily weakened it.
You are right not to touch the mixture valve. If it ran before dont mess with the mixture find the fault. It is a bugger to get the mixture right again and needs a gas analyser, no short cuts I am afraid. Wish I could check it for you, but the 'call out fee' would be a bit steep!!
I am away a couple of days so the next update might not get an early reply, someone else may well come in though.
You should hear the fuel pump click...but only if the fuel pressure has dropped a little. If the fuel accumulator and non return valave on the pump are working well the pressure will hold for some time and the pump wont need to work until here is a demand. 'Some time' is very difficult to define, some days on a very good car, quite a few hours on mine.
The coil will warm up but to get quite warm under cranking only doesnt sound right to me.
If your meter suggests a good circuit to the coil, breaking as it should, and a missing, weak or irregular spark on the strobe then get that coil changed, it isnt particularly expensive. If your is still mounted on the side of the plenum chamber I would recommend moving it to the grp firewall. It doesnt need the plenum to earth to and in the 2.8 that area isnt as well cooled as it is in the Granada so the coils can get unduly warm.
Still cant work out how it ran when you leaked petrol but doesnt now, unless it temporarily weakened it.
You are right not to touch the mixture valve. If it ran before dont mess with the mixture find the fault. It is a bugger to get the mixture right again and needs a gas analyser, no short cuts I am afraid. Wish I could check it for you, but the 'call out fee' would be a bit steep!!
I am away a couple of days so the next update might not get an early reply, someone else may well come in though.
mungral said:
to keep up the running commentary; I listened for the pump when switching the ignition on. Nothing. "Aha!" I thought, "maybe those PH experts are on to something." Cranking the engine resulted in no start as expected.
I then cracked open the filter outlet to check for fuel pressure. Sure enough, a fine spray vovered me and the engine bay.
Clean up and in frustration I turned the ignition again. Car starts first time and ticks over beautifully! I've fixed it!!
Turn engine off, and just to check my success I try to start it again. Nothing.
The pump doesn't always prime on a 2.8. I don't know how it regulates it, but it'll prime first time in the morning, then if you switch off the ignition again without starting and switch back on, it won't. Mine doesn't prime again until the engine has run.I then cracked open the filter outlet to check for fuel pressure. Sure enough, a fine spray vovered me and the engine bay.
Clean up and in frustration I turned the ignition again. Car starts first time and ticks over beautifully! I've fixed it!!
Turn engine off, and just to check my success I try to start it again. Nothing.
Mungral - have you checked the fuel pump relay? Those things are a bloody nightmare on the 2.8. I've had one allow the pump to occasionally prime (enough to create a spray if you crack an injector off) but not allow it to run for more than half a second while cranking (resulting in coughs/splutters, but no running).
Edited by Kitchski on Friday 10th February 13:22
Today I removed the cold start injector and was surprised to find it black and sooty. No spray when I cranked the starter. Aha! I thought.
Tried to measure the volts at the blue plug, 6 doesn't seem enough. Aha! I thought again.
Next stop is the temp switch. Found the brown plastic plug was missing its spring clip and the terminals were corroded and green. Aha aha!
Cleaned the terminals and put it back together with the cold start injector loosely in while I check the magic volts again. Crank the starter, voltmeter probe falls out blue plug, engine fires!!
Bolted the cold start back in and try again, starts first time. Turn it off. Starts again. And again.
Not convinced I've found the fault but we shall see tomorrow. Before then I have to replace the fuel line from filter to distributor that has decided to start leaking....
Tried to measure the volts at the blue plug, 6 doesn't seem enough. Aha! I thought again.
Next stop is the temp switch. Found the brown plastic plug was missing its spring clip and the terminals were corroded and green. Aha aha!
Cleaned the terminals and put it back together with the cold start injector loosely in while I check the magic volts again. Crank the starter, voltmeter probe falls out blue plug, engine fires!!
Bolted the cold start back in and try again, starts first time. Turn it off. Starts again. And again.
Not convinced I've found the fault but we shall see tomorrow. Before then I have to replace the fuel line from filter to distributor that has decided to start leaking....
Yep, bloody frustrating (at times) these S1s. When I broke down in Stoke on Trent in November . . . . which turned out to be the fuel pump relay - well diagnosed from a distance Glenn Robbo! . . . the breakdown guy (one of the old school mechanics) tested various things and definately had fuel getting through to the pump. We're now considering getting the pump (? - sometimes I don't get fully included in conversations) pressure tested. Looks like we could be in for a new fuel pump and adding a filter.
A bit of history from the car's documentation file that might throw some light on what has gone on: the car appears to have had fairly regular use from new until 1996 (evidence mileage and MOTs). In 2006, the car had a new owner and appears to have had problems - one of the invoices states that the car had been off the road for 10 years. Among the invoices for 2006 and 2007 are evidence that a new fuel pump, a fuel pump relay and a relay yellow pin were fitted in August 2006, in October 2006 another fuel pump fuel was fitted along with a "start" valve, in November there was an Injector test + clean; injector O ring k-jet; Bosch fuel filter,Bosch fuel accumulator, test/clean fuel injectors, fit new O rings. April 2007 - Engine flooding; fit supplied 2nd hand metering head, adjust throttle butterfly - at this point the car didn't have an MOT and was still off the road. The car passed an MOT in May 2007 and then had a Fuel sender; sender seal; fuel sender lock ring fitted at the end of the month. The car was sold the following year and then sat in a private collection for 6 years, covering only 144 miles until I bought the car in 2014.
We had a lot of problems in 2014 with hot starts (among other things)and used a fuel additive most of the time, since then fuel additive has gone in every other fill. 2015 the injectors were cleaned and rebuilt and things improved, early 2016 I had a starter motor fire and lost some of the wiring, then had major problems with the alarm system and power drain during starting. The alarm was removed and a hot start mod fitted, but the problems persisted, just before Christmas the car had an overhaul of the wiring which improved a lot of things, but not the repeat start problem.
Just writing this I can see that this car has a history of being a "little madam".
A bit of history from the car's documentation file that might throw some light on what has gone on: the car appears to have had fairly regular use from new until 1996 (evidence mileage and MOTs). In 2006, the car had a new owner and appears to have had problems - one of the invoices states that the car had been off the road for 10 years. Among the invoices for 2006 and 2007 are evidence that a new fuel pump, a fuel pump relay and a relay yellow pin were fitted in August 2006, in October 2006 another fuel pump fuel was fitted along with a "start" valve, in November there was an Injector test + clean; injector O ring k-jet; Bosch fuel filter,Bosch fuel accumulator, test/clean fuel injectors, fit new O rings. April 2007 - Engine flooding; fit supplied 2nd hand metering head, adjust throttle butterfly - at this point the car didn't have an MOT and was still off the road. The car passed an MOT in May 2007 and then had a Fuel sender; sender seal; fuel sender lock ring fitted at the end of the month. The car was sold the following year and then sat in a private collection for 6 years, covering only 144 miles until I bought the car in 2014.
We had a lot of problems in 2014 with hot starts (among other things)and used a fuel additive most of the time, since then fuel additive has gone in every other fill. 2015 the injectors were cleaned and rebuilt and things improved, early 2016 I had a starter motor fire and lost some of the wiring, then had major problems with the alarm system and power drain during starting. The alarm was removed and a hot start mod fitted, but the problems persisted, just before Christmas the car had an overhaul of the wiring which improved a lot of things, but not the repeat start problem.
Just writing this I can see that this car has a history of being a "little madam".
Hi Su,
The Fuel pump relay and pump issues may be symptoms of your problems but not the cause:
After lengthy lay-up periods of 10 + 6 years, there is a likelihood of rust forming in the fuel tank, and this is a fuel pump's worst enemy. An inline fuel filter between tank and pump will help protect it, but if there is a lot of debris, thus will gradually clog the filter and cause the pump to be starved of fuel. If thus is the case, the best remedy is either a new tank or a proper refurb. ( Richard greymrj recommends Hartlepool Radiators for their special process. )
Apart from this, there are two further potential issues which spring to my mind:
1. There is a ribbed rubber boot which encases the fuel metering unit. This can split and cause air leaks leading to mixture problems. Fairly easy to fix using PU-seal or similar ( or try to get a replacement boot. It's a Ford item, but becoming scarce.)
2. If you remove the air filter cover ( just in front of the engine ) and remove the air filter element, you will find metal stiffening plates inside the plastic casing. These plates are held in place with alloy rivets which are prone to corroding and falling out, possibly getting into the air intake and becoming ingested by the engine. The holes left by the missing rivets now allow unfiltered air into the air intake, which will gum up the rather sensitive air metering valve of the K-Jetronic Fuel Injection System.
All part and parcel of the joys of S1 ownership.
Keep calm and carry on.
Good luck,
Glen.
The Fuel pump relay and pump issues may be symptoms of your problems but not the cause:
After lengthy lay-up periods of 10 + 6 years, there is a likelihood of rust forming in the fuel tank, and this is a fuel pump's worst enemy. An inline fuel filter between tank and pump will help protect it, but if there is a lot of debris, thus will gradually clog the filter and cause the pump to be starved of fuel. If thus is the case, the best remedy is either a new tank or a proper refurb. ( Richard greymrj recommends Hartlepool Radiators for their special process. )
Apart from this, there are two further potential issues which spring to my mind:
1. There is a ribbed rubber boot which encases the fuel metering unit. This can split and cause air leaks leading to mixture problems. Fairly easy to fix using PU-seal or similar ( or try to get a replacement boot. It's a Ford item, but becoming scarce.)
2. If you remove the air filter cover ( just in front of the engine ) and remove the air filter element, you will find metal stiffening plates inside the plastic casing. These plates are held in place with alloy rivets which are prone to corroding and falling out, possibly getting into the air intake and becoming ingested by the engine. The holes left by the missing rivets now allow unfiltered air into the air intake, which will gum up the rather sensitive air metering valve of the K-Jetronic Fuel Injection System.
All part and parcel of the joys of S1 ownership.
Keep calm and carry on.
Good luck,
Glen.
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