Jimsl78

I just scored a ventolux pump that is in nice condition (other than the rubber seal that has turned to dust).
I googled "repair ventolux pump" and read that you can make a replacement seal from a piece of heavy leather or some other type of pump seal that has a suitable diameter for a retrofit. Has anybody tried this?

Jimsl78

So no takers?
Anyway, I went ahead and experimented with a home made leather seal and my half-assed attempt worked surprisingly well!
I used a piece of boot leather for the material.
The idea is to cut a washer 1/8 ' larger than the bore diameter, then soak it it water overnight to let it soften and swell. Not wanting to wait I skipped that part and just doused it in oil, then forming a "cup" shape pushing the edges forward into the bore. I got it to seal with a number of pump strokes and adding more oil. It took about 10 minutes before it could hold pressure with my thumb blocking the hose opening, then I went to try inflating a tire. My old pump now works well enough to pump a tire up to 44 PSI.
here's how it looks..........

* the next washer I make will be by this process........https://www.youtube.com/watch?v=6xFhThdnYqE

By the lack of response to the first post, I might re-post this as a tutorial once I perfect the process.

non-fixie 

Thanks! I bought a similar pump yesterday, with a similar problem.

Len S

Congratulations, you have just made a 1050's bike pump just like the millions that were made in that period! They really worked fine with the leather plunger. good fix.

Jimsl78

Len S
I'm not familiar with the term "1050's bike pump" but thanks for the encouragement.
The next trick I want to try is smoothing out the dents with a wooden dowel. I will post a pic as this pump I procured progresses to perfect pristineness (and a peck of pickled peppers).

orcas island 

Nice - I will try this out. I have 2 or 3 dead pumps that this trick might revive!

Prowler 

I didn't have time to answer your OP but I've made a 'pump leather' too which has worked nicely. Search on pump leather a few times and you'll find useful info. IIRC I took a similar path; cut the leather disk and soaked overnight. For my pump I found that the ID of a bit of 3/4" copper pipe was just right and I found a rod that fit that ID with clearance for the leather. I smoothed the edges on the end of the pipe and the end of the rod and gently 'rammed' the leather down into the pipe with the rod, nice and even and centered to shape the leather. I set that over on the furnace to dry for a few days.

I then took a very sharp knife and trimmed the leather around the rod so that was quite even. I removed the new pump leather and trimmed a bevel on the ID of the leather so there was a wee edge in contact with the pump wall. I think there is some optimum wall length for the pump leather - too long and it wont hold pressure, too short and it wont engage the pump wall well. I've not found that (my pump is just cosmetic, I just wanted it to actually pump). You would have to try several trial-n-error pieces to find that just right design. If you're lucky and have the old leather you could copy that. I did not.

Then oil it, install and pump away. I also found that pump pressure tends to seat the new leather and it works better. Cheers.

cyclingarri

I have the exact same pump with the same problem. I will be using this tutorial when I get around to fixing this thing. So def. will be asking some ques. Hopefully you can help me out. It maybe to late for this but...I removed the dent in my pump by using the seat post and tapping into the pump with a mallet. Worked great and dent smoothed out pretty good.

jj1091

I repaired mine with a scrap of leather from an old belt I had laying around. It worked just fine without any period of overnight shaping of the cup, just had to get the size right. The plastic screw-on plunger guide on mine crumbled, however, so even though it will pump up a tire to decent pressure it doesn't work smooth enough to be much more than a decoration. Good luck on yours.

cyclingarri

* the next washer I make will be by this process........
By the lack of response to the first post, I might re-post this as a tutorial once I perfect the process.[/QUOTE]

Did you tape that tutorial on this yet? I hope it includes a breakdown of the inner parts. I took mine apart some black washer broke into pieces and I don't know in what order anything was in. Let me know I would really appreciate it. Thanks

qcpmsame 

He hasn't had any forum activity since '15, shortly after this post.

If you don't mind mixing parts between manufacturers, check the diameter (I.D.) of your pump's tube, you can still buy the Silca leathers for their frame and floor pumps. I found the old school Impero frame pump's leathers on eBay.

Bill

Velocivixen

I had this very same problem with a vintage pump. Initially, I soaked the original piece of leather in olive oil to soften it, then reinstalled. It worked but I wanted something else. After long search and driving from place to place I found 2 sources for leather "cup" washers: 1. Vintage Coleman lanterns used them (sorry I don't recall exactly how they were used, but they were used), and 2. Home beer brewing supply places sell the leather cup washers, although in my case they were a little too big. I guess I could have cut them down a bit.

Good luck.

cyclingarri

After a whole lot of searching I found this site, that has these replacement parts for pumps. I am going to purchase and play/modify them around if needed. What do you think? https://www.bikeparts.com/BPC306098/...leather-washer)

qcpmsame 

It would be a question of the diameter of your existing leather against the one you linked. If the size and shape are close enough it might be worth the $8.00 to find out. One other place to try and find some information is the videos on You Tube, type in your pump's manufacturer and model to see if there are any rebuild vids available for it. There are a great deal of useful instructional videos there for just about any topic you can think of. I found many for the Silca pumps of every variety to instruct you on various maintenance topics.

I'm not familiar with your pump brand, so if I were you I would make a new thread and lay it out so the more knowledgeable here can give you input on the matter. You could get more attention with a new presentation of your question. Best of luck on finding the leather, don't discount the reply above about reconditioning the leathers also.

Bill