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Author Topic: Crappy running 8V71 FINALLY Solved!!  (Read 3782 times)

Offline OneLapper

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Crappy running 8V71 FINALLY Solved!!
« on: February 11, 2009, 08:06:53 PM »
After spending 9 hours running new 1/2" od air line to replace the oem copper tubing fuel line, the new line didn't work either.

I should have checked this FIRST.  On top of the fuel tank, the reducer that the 90 degree elbow is fitted to was completely plugged with....  well, tarry junk.

BTW, It was much more difficult to prime the system with 1/2" line compared to the 3/8", but I got it.

Engine runs!

Off to Kershaw SC on the 21st.
« Last Edit: February 11, 2009, 09:03:36 PM by OneLapper »
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Offline Barn Owl

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Re: Crappy running 8V71 FINALLY Solved!!
« Reply #1 on: February 11, 2009, 10:41:11 PM »
Great to pass along this type of info. These are the type of things that can drive us crazy and leave us stranded. Thanks for sharing your experience.
L. Christley - W3EYE Amateur Extra
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Offline gm4106

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Re: Crappy running 8V71 FINALLY Solved!!
« Reply #2 on: February 12, 2009, 05:53:26 AM »
Yes we always like to see the fix on here. But to find the quick and easy way is something else
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Offline steve5B

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Re: Crappy running 8V71 FINALLY Solved!!
« Reply #3 on: February 12, 2009, 05:58:14 AM »


   Onelapper,


    Was that problem that you discovered on the return line?  I wondering now if the MCI'S have that also.

    As barnowl stated thanks for sharing!


    Steve 5B.....
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Offline OneLapper

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Re: Crappy running 8V71 FINALLY Solved!!
« Reply #4 on: February 12, 2009, 08:50:31 AM »
The clog was in the supply line, right on the top of the fuel tank where the 90 elbow attaches to the fuel pickup tube in the tank.  Just drove 100 miles in it.  It has never run so well in all the time I've owned it!  Of course, it still has a bad cylinder so the blowby is about as bad as it can get!
« Last Edit: February 12, 2009, 01:24:54 PM by OneLapper »
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Offline Len Silva

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Re: Crappy running 8V71 FINALLY Solved!!
« Reply #5 on: February 12, 2009, 11:25:11 AM »
Let me ask the DD experts here.  If the fuel supply is restricted by a clog like this or just dirty filters, then it seems that the return fuel would be greatly reduced.  Will this damage the injectors by reducing the cooling effect of the fuel?

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Offline gus

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Re: Crappy running 8V71 FINALLY Solved!!
« Reply #6 on: February 12, 2009, 05:11:30 PM »
Thanks for the follow up. Too often we never hear about fixes to problems.

This same problem showed up on a bunch of Cat 3208 diesel engines a few years back. I happened to have one in an antique fire truck and it had the same problem.
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Offline Charles in SC

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Re: Crappy running 8V71 FINALLY Solved!!
« Reply #7 on: February 12, 2009, 07:26:47 PM »
What is happening in Kershaw on the 21st?
I am near Spartanburg.
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Offline Dreamscape

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Re: Crappy running 8V71 FINALLY Solved!!
« Reply #8 on: February 13, 2009, 12:16:23 PM »
What was the goo made of? Any ideas?

Just curious that's all!

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Offline OneLapper

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Re: Crappy running 8V71 FINALLY Solved!!
« Reply #9 on: February 13, 2009, 12:21:20 PM »
I 'host' driving events at different race tracks on the east coast.  They're small events, but if you'd like to see Spec Miatas to Challenge Series race cars and everything in between, feel free to stop by at Carolina Motorsports Park in Kershaw, SC.  Plenty of room for buses, too!  I'm bringing my 4106 down and picking up another 4106 from GA to drive back to CT.  I'm cleaning up that one and I'll be either parting it out or selling it whole.

We're at the track Monday Feb 23 & Tues 24.  If you stop by, tell the gate person your will the "Mark DaVia's Driving Experience".  I'm friends with the owners of the track so they know to expect buses at my events!

I'm hoping to stop by for a short visit at GM4106's in Mount Holly NC on my way down.  Looks like I'll be passing his place late afternoon on Sunday, the 22nd.

Mark
« Last Edit: February 13, 2009, 01:47:36 PM by OneLapper »
OneLapper
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Offline OneLapper

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Re: Crappy running 8V71 FINALLY Solved!!
« Reply #10 on: February 13, 2009, 12:31:19 PM »
The goo was actually crispy.  I wasn't able to determine if it was organic, but it was certainly years of diesel crude that built up on the obstruction at the  point fuel flowed around it.  Eventually, while driving it of course, the engine just ran out of fuel and stopped.  I had the worst time repriming the engine and eventually hooked up a fuel jug to get it to run.

Now it runs better than ever!

Wait till you see my muffler bypass.  Pictures next week on that.

Mark
« Last Edit: February 13, 2009, 01:46:43 PM by OneLapper »
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Offline Sammy

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Re: Crappy running 8V71 FINALLY Solved!!
« Reply #11 on: February 13, 2009, 01:22:35 PM »
That "goo" might have been algae, believe it or not. When diesel fuel sits in a tank for a long time,
algae can form in the tank. Glad to hear you're up and running.  8)