EMERGENCY PULLER

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Steggy
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EMERGENCY PULLER

Post by Steggy »

No, this is not about an unplanned visit to the dentist for a bad toothache. It’s about making a tool from a piece of scrop (“scrop” is a made-up word used to describe a piece of drop that is also scrap) and a big bolt. First some background...

The shop had a Volkswagen Diesel come in with the owner complaining about a lack of power. I was somewhat astounded to learn that anyone would use the word “power” in connection with a Volkswagen, especially one with a Diesel engine. However, this particular VW was indeed quite ill, as it could barely manage 40 MPH with the pedal to the metal. The problem was traced to the high-pressure fuel pump, which evidently had converted itself into a medium pressure pump, starving the engine of fuel.

Getting at the pump is not a problem, but removing it while lacking the right tools is. The pump is driven by a timing belt, which was easy enough to remove. The pump’s pulley is bolted to a hub that fits on the pump’s tapered shaft. Extricating the pulley was also easy. So far, so good.

The pump is mounted to the back face of the engine’s timing case through a small hole that acts as a register. VW, in their infinite wisdom, decided the hub should be bigger in diameter than the register hole, which meant the hub would have to be removed before the pump could be pulled. As I noted, this hub is on a tapered shaft...and is retained by a fairly substantial—by Volkswagen standards—nut that was cranked on with a gazillion pounds-feet of torque. An impact wrench took care of removing the nut, but that hub seemed to be welded to the shaft. Using a conventional jaw puller to extract the hub was out of the question. There wasn’t enough clearance behind the hub to get the jaws in place. A puller was needed that could be bolted to the hub.

The mechanic dug out a “universal” puller that was supposed to work with this pump, but Volkswagen apparently hadn’t been consulted when this particular puller was being designed. The three holes in the puller body didn’t align with the threaded holes in the hub. It turned out a tool made specifically for pulling this particular hub was available, but it would take a week to 10 days to get one. That wasn’t acceptable. (Oddly, a replacement pump was available in about four hours after it was ordered.)

As luck would have it, I was in the shop at the time and soon got dragged into the situation. Being the nice guy I (mostly) am, not to mention the only one in the shop who knows how to make useful items from scrap iron, I told the mechanic I could cobble together a puller if I could find suitable materials. Said materials were available, and here is the result:

Pulley Hub Puller
Pulley Hub Puller
hub_puller01_reduced.jpg (226.02 KiB) Viewed 812 times

The body of the puller is made from a piece of 3/4" × 1-1/4 CF steel that I had laying around. Some dings in the side of it suggest it was once beaten on with a sizable hammer. Not a problem; the dings give the puller some character. 8)

The two small bolts actually belong to the puller that was supposed to fit the pump’s hub, but didn’t. These bolts are metric (no surprise) and, luckily, threaded into the hub’s tapped holes. I had to counterbore the bolt holes in the body to accommodate the bolts’ length. The counterbore diameter is just enough to give clearance for the socket needed to tighten the two bolts.

Pulley Hub Puller Body
Pulley Hub Puller Body
hub_puller02_reduced.jpg (200.96 KiB) Viewed 812 times

The draw bolt was made by doing some minor machining to the end of a 3/4"-16 grade eight capscrew I found in the shop bolt assortment.

Pulley Hub Puller Draw Bolt
Pulley Hub Puller Draw Bolt
hub_puller03_reduced.jpg (177.32 KiB) Viewed 812 times

The pilot on the bolt’s end prevents it from wandering off-center during use—it closely fits the center-drill in the pump shaft’s end.

Having found this particular bolt was fortuitous. Its relatively large diameter and being grade eight meant that it was strong enough to resist a lot of force—we really had no idea what it would take to extract the hub. Being 16 threads per inch helped with needed mechanical advantage. The mechanic reported that the hub popped off using a 24" breaker bar and socket to turn the draw bolt.

The owner got their VW back in three days instead of 12 or 13. I was a hero for a few hours...and went back to being the shop bum the next day. :D

***
EDIT: Fixed a typo.
Last edited by Steggy on Wed Mar 29, 2023 4:35 pm, edited 1 time in total.
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Music isn’t at all difficult.  All you gotta do is play the right notes at the right time!  :D
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Harold_V
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Re: EMERGENCY PULLER

Post by Harold_V »

Well done!
H
Wise people talk because they have something to say. Fools talk because they have to say something.
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Bill Shields
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Re: EMERGENCY PULLER

Post by Bill Shields »

Make a few and put on ebay
Too many things going on to bother listing them.
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liveaboard
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Re: EMERGENCY PULLER

Post by liveaboard »

Nice looking for a one use tool.
I think I make a new puller for every job... but mine aren't as pretty.
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Steggy
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Re: EMERGENCY PULLER

Post by Steggy »

Harold_V wrote: Wed Mar 29, 2023 3:16 am Well done!
H
Thanks!

Bill Shields wrote: Wed Mar 29, 2023 4:15 amMake a few and put on ebay
Do you think I could charge more if the body had some hammer dings in it? :D

liveaboard wrote: Wed Mar 29, 2023 12:37 pm Nice looking for a one use tool.
I think I make a new puller for every job... but mine aren't as pretty.

This puller might be good for a few more uses, although I only guaranteed it for one. The limitation on it would be the relatively soft threads in the body. The draw bolt seems to be around 28-30 Rockwell C, based on the way it cut as I was facing the end. The body is 1018 CF steel, so its hardness would be in the Rockwell B range. Guess what will wear out first.

Years ago, I made an “emergency” MacPherson strut spring compressor, with a piece of hardware store threaded rod running through a 440 stainless pin to pull the two arms together (the 440 stainless was a sample given to me by a Jorgensen Steel rep—the rest of the tool was made from scrop). It was supposed to be a one-use tool, but ended up surviving nearly 10 years of use before the threaded rod finally lost its threads.

I suspect this emergency puller will see more use. HP fuel pump maladies are apparently not uncommon with VW Diesels. It figures! The owner saves money via reduced fuel consumption, only to have to spend it to have the pump replaced when it goes on the fritz. :D
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Music isn’t at all difficult.  All you gotta do is play the right notes at the right time!  :D
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Bill Shields
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Re: EMERGENCY PULLER

Post by Bill Shields »

For someone who cannot make one, and will only need it once in a blue moon..do not be critical of your beautiful work
Too many things going on to bother listing them.
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Steggy
Posts: 1976
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Re: EMERGENCY PULLER

Post by Steggy »

Bill Shields wrote: Wed Mar 29, 2023 8:22 pm For someone who cannot make one, and will only need it once in a blue moon..do not be critical of your beautiful work
I’ve got a sneaking suspicion most of the folks who would regularly use one already have one. Making one suitable for sale would involve more work and time than I think would be profitable.
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Music isn’t at all difficult.  All you gotta do is play the right notes at the right time!  :D
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