Roush 8 stack fuel leak

My Roush 8 stack injection system has started leaking at the end of the fuel rail. It's dripping right onto the distributor. I was lucky I noticed it before heading out on my first drive of the season. I'm assuming there's a bad o-ring at the end fitting. Before I start pulling things apart I thought I'd ask if anyone has experience with this setup and can tell me what I'll find in there. I can't seem to locate any diagrams anywhere. Thanks.
 

Markus

SPRF40
Lifetime Supporter
Hi Daryl,

please see attached pictures > unfortunately I don't have the TMW pic with better resolution! > in the left bottom corner it says "M6 Screw-apply loctite tighten, then back off 1/2 turn" for one bolt, for the second bolt it says "M6 Screw-apply loctite tighten"....

If it is the O-Ring you should check/replace the other O-Rings as well (see second pic).

I would check the two bolt which are descibed above.

Good luck.

Markus
 

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Hi Daryl,

I've got the same EFI stack and I had a similar problem when I've tried to start the engine after 1 year stop.

Fuel was leaking (big leaks) from the center o-rings.

In fact it was just the fuel regulator which was locked. I disassembled it cleaned it and retried to start the engine. No leaks at all !

So of course it could a leak from the screws as Markus said or from an o-ring but if your car didn't run since months the fuel regulator locked could be an idea to check.

ROBY427
 
Hi Daryl,

please see attached pictures > unfortunately I don't have the TMW pic with better resolution! > in the left bottom corner it says "M6 Screw-apply loctite tighten, then back off 1/2 turn" for one bolt, for the second bolt it says "M6 Screw-apply loctite tighten"....

If it is the O-Ring you should check/replace the other O-Rings as well (see second pic).

I would check the two bolt which are descibed above.

Good luck.

Markus

Hi Markus,

If you ever have the o-rings reference I'm very interested to get it... We never know...

Thanks,

ROBY427 (do you plan to go to Le Mans Classic in July ?)
 
I have the exact same TWM setup and like all rubber products in fuel lines and fittings you have to keep them lubricated/wet with fuel to preserve the rubber. If they sit over the winter you better espect to see leaks or wet fuel lines(armouredlines). The rubber dries out and begins to crack. When I bought my AN lines off of Ebay I had to put them through their bend radius to listen for the cracking. Those of course were thrown out. It onlyu takes a few weeks fpor them to dry out. You should adapt a sche3dule to routinely run the fuel pumps every week or two for several minutes to really set the o rings and hoses liners. I bought my fuel lines 6-7 years ago and I try to drive/run the engine of my car every few weeks(Georgia weather permitting). In all these years of use I have only changed one of the hoses to the fuel pumps and that one change allowed a small chunk of line to lodge in the high pressure pump and cause it to stop(sitting at a red light no less).
It is about time to change the lines in total due to the wear of the liners by the fuel additives. All rubber fuel parts will wear out from lack of use or from constant use. I just know that the more you use them the longer they will last.
If you are talking about the end of the fuel rails toward the distributor, and you have a Ford engine, then you are talking about the fuel delivery line or the end rail where the regulator lives. I have never removed the fittings to the regulator, so I can't help you there. TWM was bought out by Borla. I can't see any exploded diagrams on their site.
 

Markus

SPRF40
Lifetime Supporter
Hello Roby427,

the fuel rail O rings should be size 112. The material is Buna N.

Yes, I'm attending to LMC in July.

Are you going there as well?

Regards,

Markus
 
Hello Roby427,

the fuel rail O rings should be size 112. The material is Buna N.

Yes, I'm attending to LMC in July.

Are you going there as well?

Regards,

Markus

Hi Markus,

Thanks for the o-ring info.

Yes I'm going to LMC with the GT40. Hope we could meet there (I could give you my cell phone number in PM).

ROBY427
 

Dave Bilyk

Dave Bilyk
Supporter
+1 to Bills explanation. This happens with Holley transfer tubes too. Over the 13 years I've had my DAX, fuel leaks after winter layup from fuel hose connections, Holley transfer tubes and float covers all on separate years. The message is to check for leaks before you drive, and keep fuel system primed during layoff.

Dave
 

Markus

SPRF40
Lifetime Supporter
Hi Daryl,

see attachment.

Markus
 

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