More surging issues

[srgtlord]

So after another extended trip on the highway the old 85 golf is experiencing surging issues at part throttle. At first I thought the pump bolts loosened up but I checked all of them and they were fine. I have 2 educated guesses for this one on what the issue is

1. Timing belt
The belt probably has over 65,000 miles on it by now and after popping the cover off I see oil on the belt

2. The injection pump
I noticed the pump was leaking again after 10 years

Ill do the timing belt job and report back

[fatmobile]

Which bolts did you check?
 The ones holding the mounting bracket to the block?

[srgtlord]

I checked the bolts holding the pump to the mounting bracket. Hmm I might have to check the ones holding the bracket to the block

[fatmobile]

yep,
and they are hard to get to.
 Those 2 bolts are also used to adjust where the belt rides on the sprocket.

 I always blue locktite them after the belt is riding in the right place.

When they are loose you might also feel a vibration on the accelerator/your foot.

[Rabbit79]

Which bolts did you check?
 The ones holding the mounting bracket to the block?

Seconded. It's happened to me before.

[RustyCaddy]

On the very off chance what i had experienced might apply to your situation, the bolt holding the sprocket to the crankshaft came lose once and backed out a couple of millimeters. The sprocket was traveling slightly but still rode the woodruff key.  The engine would advance and retard, back and forth so sometimes it felt like it was surging.

[srgtlord]

Well I'll be damned.... 3 of the 4 bolts holding the pump bracket to the block are gone and the 4th is barely threaded on.... Holy crappers.......

[ORCoaster]

Caught in the nick of time.  That could have be an exploding momment if that IP came unbolted.

[fatmobile]

3 out of 4 and the last one was loose.
 That's bad.
 So the pump was bolted on,.. to a bunch of loose brackets, ha.
 Could have been a much worse ending.

 Blue  locktite them back in.

[srgtlord]

Yeah I'm going to steal the bolts off my spare engine and put them in this weekend. This is looking like a Sunday afternoon project

[ORCoaster]

Just go to the hardware store and get some new bolts.  Easier than removal from engine B for engine A.  You have one to use as a match. 

They do sell those metric bolts here in America you do know that?!!

[srgtlord]

Yeah but the rust prevention/coating is much different on the hardware store bolts I've noticed. Even the "stainless" bolts start rusting in a few years. But overall to save on the headache of pulling apart the spare engine I'll just pick some new bolts up as suggested

[ORCoaster]

Don't worry about the rust, they will have a good coating of oil/diesel on them most of the time. 

[fatmobile]

You have to remove the oil on the bolts and holes to get the locktite to stick.

[srgtlord]

Welp got the whole thing back together and running like a champ now