[mustangmod69]

The mechanical fuel pump failed this weekend in my 69 Mustang. I simply want to replace the $21 mechanical fuel pump and not go electric or anything, but when I went to install the new pump, the bolt on the right side does not tighten down and simply spins and spins. What caused this and how do I fix it with the motor in the car?

 

[paul289]

Sounds like you stripped the hole. If that's the case, you may need a new timing cover. To replace it, you'll have to remove all the front accessories, but you won't have to pull the engine.

 

[Ivy66GT]

Helicoil the stripped hole.

 

[hipowerdad]

Helicoil the stripped hole.

+1

 

[Print Dad]

Hello mustangmod69,
The guys are correct saying you may need to h-coil
but I always like to try the simple things -sometimes you
get lucky

I would remove the bolt and try putting a washer or to behind the head
(shorten the bolt length) and of course my second try would be a new bolt. Like I say - worth a try - both are simple.
If this doesn't do the trick - -you likely will have to go the "Heli route

I hope this works
Print DAd

 

[mustangmod69]

Thanks all. I never done a helicoil, looks like I'd need to be able to fit a drill down there. I tried a different bolt and did not tighten it as much as I thought I should be able too, so far so good but I'm afraid after time the vibration might loosen it as well since the other one wasn't tightening, time will tell. Thanks again

 

[Ivy66GT]

Depending upon what size your hole is now you may well have to drill out the semi-stripped thread that is in there. You then use a special tap with threads that match the helicoil you want to screw in place. Once the coil is in place the bolt will screw into the helicoil threads as original.

 

[Tominator]

The Helicoil will be about the same expense as a used timing cover....

And since you asked....how old is that timing gear set.....that may have nylon gears.....>

One 'get you by' option is to use a self tapping bolt.

Putting in a helicoil in that position may be a bit taxing for even us experienced folks, but before if I took the cover off and paid a shop to insert the coil, my consideration would include the other parts subject to wear that would need removed for access.

 

[Ivy66GT]

And since you asked....how old is that timing gear set.....that may have nylon gears.....>

If its still the original nylon gear then probably half of those nylon teeth have broken off by now!

Helicoil kits are not expensive. You can buy them on Amazon for under $20. I don't recall what size you would need but its something close to this one: Amazon.com: Helicoil 5521-5 5/16-18 Inch Coarse Thread Repair Kit: Automotive


Here is one version of how you do it:
http://www.roadstarmagazine.com/2004/03/how-to-use-a-helicoil/

 

[rex1965]

You could also try a longer bolt, they are a 3/8" bolt NC grade 5, but I would first insert a piece of wire into the hole and see how much depth you have then use a bolt just a little bit less like maybe a 1/8" less, and if you don't have room for a longer bolt, then get a metric bolt with the same pitch (threads per inch)I realize that metric are not in inches, but if you lay the old bolt against a metric one threads to threads you will see one that is so close it should work, and slightly larger diameter, you may have to tap it for the metric bolt. My 2 cts. Good Luck.