4.5 Fuel rail refit - LEAKS
Discussion
Can anyone help? I have fuel leaks around the top injector seats on refitting and can't cure.
New o rings fitted with red grease..
Fitting the rail/injectors is very difficult as the whole assemble doesn't naturally align. You have to 'bend' the injectors to get them into their seats. I found the best way was to fit one bank's injectors into the TBs and the other bank's into the rail. Then push the fuel rail and its injectors into the TBs and then roll the fuel rail over to push the other injectors into their seats with a 32mm spanner on the fuel rail and a few gentle taps with a rubber mallet..
Clamping down the rail with the two roof-shaped steel strips using the 4 capheads is a recipe for stripping the threads in the alloy TB castings. When fixed I noticed that there is a significant misalignment between throttle body injector bore centreline and fuel rail injector cup bore centreline so that when everything is bolted down the injectors don't line up and sit canted over - but they have the same orientation on both banks. It looks as if the angle between cups on the rail is too wide - or the rail needs to go down another 5mm. I've stripped and refitted several times today and no way will the centrelines align. I also notice a couple of injectors are clamped solid while others can be rotated. The ones that are solid are pressing metal on metal into the rail (grooving in the rail) which looks bad - typical TVR tolerances again? I've tried increasing clamping pressure by putting thin pieces of metal under the tie-down strips, but doesn't seem to make any difference re the leaks.
Is there a secret to fitting? Or is it hit-and-miss - try until no leaks. Is the misalignment standard - or am I enjoying one of those treasured TVR moments??!!
New o rings fitted with red grease..
Fitting the rail/injectors is very difficult as the whole assemble doesn't naturally align. You have to 'bend' the injectors to get them into their seats. I found the best way was to fit one bank's injectors into the TBs and the other bank's into the rail. Then push the fuel rail and its injectors into the TBs and then roll the fuel rail over to push the other injectors into their seats with a 32mm spanner on the fuel rail and a few gentle taps with a rubber mallet..
Clamping down the rail with the two roof-shaped steel strips using the 4 capheads is a recipe for stripping the threads in the alloy TB castings. When fixed I noticed that there is a significant misalignment between throttle body injector bore centreline and fuel rail injector cup bore centreline so that when everything is bolted down the injectors don't line up and sit canted over - but they have the same orientation on both banks. It looks as if the angle between cups on the rail is too wide - or the rail needs to go down another 5mm. I've stripped and refitted several times today and no way will the centrelines align. I also notice a couple of injectors are clamped solid while others can be rotated. The ones that are solid are pressing metal on metal into the rail (grooving in the rail) which looks bad - typical TVR tolerances again? I've tried increasing clamping pressure by putting thin pieces of metal under the tie-down strips, but doesn't seem to make any difference re the leaks.
Is there a secret to fitting? Or is it hit-and-miss - try until no leaks. Is the misalignment standard - or am I enjoying one of those treasured TVR moments??!!
This is from the workshop manual.
1. Ensure to either P.T.F.E tape or pipe seal the bungs first.
2. Next fit bungs to all 5 threaded holes on the fule rail.
3. Lubricate seals in fuel pressure regulator
4. Then fit to fuel rail and retain with M5 x 12mm long socket head set screws + pad washers.
5. Lubricate injector seals.
6. Fit injectors to fuel rail.
7. Next lubricate all injectors and fit fuel rail to intakes.
8. Attach with 4 M5 x 15 bolts + pad washers.
9. Fit throttle connecting rod.
10. Fit purge line to intakes.
11. Fit 4 way adaptor to purge lines.
Hope it all makes sence to you. To me there seems a lot of P.T.F.E tape, lubrication and pad washers.
1. Ensure to either P.T.F.E tape or pipe seal the bungs first.
2. Next fit bungs to all 5 threaded holes on the fule rail.
3. Lubricate seals in fuel pressure regulator
4. Then fit to fuel rail and retain with M5 x 12mm long socket head set screws + pad washers.
5. Lubricate injector seals.
6. Fit injectors to fuel rail.
7. Next lubricate all injectors and fit fuel rail to intakes.
8. Attach with 4 M5 x 15 bolts + pad washers.
9. Fit throttle connecting rod.
10. Fit purge line to intakes.
11. Fit 4 way adaptor to purge lines.
Hope it all makes sence to you. To me there seems a lot of P.T.F.E tape, lubrication and pad washers.
c3ber said:
This is from the workshop manual.
1. Ensure to either P.T.F.E tape or pipe seal the bungs first.
2. Next fit bungs to all 5 threaded holes on the fule rail.
3. Lubricate seals in fuel pressure regulator
4. Then fit to fuel rail and retain with M5 x 12mm long socket head set screws + pad washers.
5. Lubricate injector seals.
6. Fit injectors to fuel rail.
7. Next lubricate all injectors and fit fuel rail to intakes.
8. Attach with 4 M5 x 15 bolts + pad washers.
9. Fit throttle connecting rod.
10. Fit purge line to intakes.
11. Fit 4 way adaptor to purge lines.
Hope it all makes sence to you. To me there seems a lot of P.T.F.E tape, lubrication and pad washers.
1. Ensure to either P.T.F.E tape or pipe seal the bungs first.
2. Next fit bungs to all 5 threaded holes on the fule rail.
3. Lubricate seals in fuel pressure regulator
4. Then fit to fuel rail and retain with M5 x 12mm long socket head set screws + pad washers.
5. Lubricate injector seals.
6. Fit injectors to fuel rail.
7. Next lubricate all injectors and fit fuel rail to intakes.
8. Attach with 4 M5 x 15 bolts + pad washers.
9. Fit throttle connecting rod.
10. Fit purge line to intakes.
11. Fit 4 way adaptor to purge lines.
Hope it all makes sence to you. To me there seems a lot of P.T.F.E tape, lubrication and pad washers.
Your getting a little clued up Mick, Bed time reading
TooTall Paul said:
c3ber said:
This is from the workshop manual.
1. Ensure to either P.T.F.E tape or pipe seal the bungs first.
2. Next fit bungs to all 5 threaded holes on the fule rail.
3. Lubricate seals in fuel pressure regulator
4. Then fit to fuel rail and retain with M5 x 12mm long socket head set screws + pad washers.
5. Lubricate injector seals.
6. Fit injectors to fuel rail.
7. Next lubricate all injectors and fit fuel rail to intakes.
8. Attach with 4 M5 x 15 bolts + pad washers.
9. Fit throttle connecting rod.
10. Fit purge line to intakes.
11. Fit 4 way adaptor to purge lines.
Hope it all makes sence to you. To me there seems a lot of P.T.F.E tape, lubrication and pad washers.
1. Ensure to either P.T.F.E tape or pipe seal the bungs first.
2. Next fit bungs to all 5 threaded holes on the fule rail.
3. Lubricate seals in fuel pressure regulator
4. Then fit to fuel rail and retain with M5 x 12mm long socket head set screws + pad washers.
5. Lubricate injector seals.
6. Fit injectors to fuel rail.
7. Next lubricate all injectors and fit fuel rail to intakes.
8. Attach with 4 M5 x 15 bolts + pad washers.
9. Fit throttle connecting rod.
10. Fit purge line to intakes.
11. Fit 4 way adaptor to purge lines.
Hope it all makes sence to you. To me there seems a lot of P.T.F.E tape, lubrication and pad washers.
Your getting a little clued up Mick, Bed time reading
Morning Paul. Yes its the pink book that found its way to my sticky mits.
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