[DorkMissile]

I am trying to verify - is GM PN 12618337 the correct fuel line kit when updating from the LT1 to LT4 HPFP?

[Dysan911]

That's the cross over pipe. Technically it's a 1 use only because of a seal coating on the threads but many just reuse it without a problem.

[DorkMissile]

The PN I gave is correct?

[Dysan911]

Originally Posted by DorkMissile

The PN I gave is correct?

yes it is...

[L78toLT1]

Has anyone experienced problems reusing their original fuel line? I plan to reuse mine unless someone talks me out of it. Pulling the blower back off to access that line would be a minor PITA.

[KingLT1]

I was told by a few different sources that its fine to reuse. Ted Jenetty being one of them.

[Dysan911]

Yep and I reused mine as well based on Ted's advice. No issues at all.

[laynlo15]

I didn't reuse mine on any of the times I've changed pumps. I have a good buddy that helps me and he works for GM. He said GM recommends it because they've had some problems so I just go ahead and change them each time 80.00 bucks total is not an issue to me if there is any chance something could happen. There are 2 pipes you need.
12677004 $25.93 ($38.42) and 12677002 $44.13 ($65.38) That's what I paid. Retail is of course the higher prices I listed.

[KingLT1]

Just gonna update: We had to pull my car off the dyno today because there was a fuel smell. Guess what, that cross over line was leaking. Said mine was the first that ever had that problem. So the line will be replaced.

[Dysan911]

Originally Posted by KingLT1

Just gonna update: We had to pull my car off the dyno today because there was a fuel smell. Guess what, that cross over line was leaking. Said mine was the first that ever had that problem. So the line will be replaced.

Wow what an opportune time for that to go.

It must have known we were talking about it. 😜

[KingLT1]

My thoughts exactly. Lol

[DorkMissile]

I wonder if one could source the sealant if you could re-apply it?

[DorkMissile]

I have a friend who is a technician at the GM proving grounds in Milford (GMs R&D center) and I called him to ask. He says he has changed hundreds of pumps over the years of DI testing.

He says the purple / blue stuff on the threads is just a whiteness die. It’s to show the fitting was installed and tightened correctly for warranty / insurance reasons.

Now he says that they have re-used lines multiple times with no issues. Says the trick is to initially finger tighten slowly and to get the original “dimple” that was made upon the original torquing to seat in the seal. If they aren’t lined up exactly the same, it will create a new “dimple” and it will cross at two points with the original dimple, and will leak where the two cross.

He says they have probably a higher than 90% success rate with reusing the lines, and they have test mules (trucks for running around the area) that have had multiple pumps over the years with the same lines, but as he stated, nobody really knows the long term effects. Will the connection stay sealed as good as a new one for 200,000 miles? They dont know.

Just like us, they are trying to save the money too. Like he said, if they used a new line for every pump swap they would have added millions of dollars in parts and downtime.

I will more than likely give it a shot with reusing the lines.

[DapperDan]

Originally Posted by KingLT1

Just gonna update: We had to pull my car off the dyno today because there was a fuel smell. Guess what, that cross over line was leaking. Said mine was the first that ever had that problem. So the line will be replaced.

Dang now I will worry about this, thats what I get for being a cheap ass...lol