Speedseal Life PTFE bearing disk - supplier and dimensions

J

john0740

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Was the disk size the same in all models? Assuming so, would appreciate if someone could post the dimensions - will avoid me taking it apart to measure!

I am presuming that this was a bought-in part so should be reasonably easy to find. Supplier links anyone?

(I am assuming that it would not be necessary to try to cut one from PTFE sheet)

thanks
 
Hi, there are a few threads floating around about Speedseal spares, but I have just made some spares for my 3YM30 which were 40.5 mm OD and if I recall correctly, 11.4mm hole . My mate with a Volvo has a different size but same thickness. So to answer your question there are at least 2 variants! The thickness was the same .. the genuine spare measured 2.3mm thick but I could only get 2mm thick PTFE sheet.(ebay) I have checked the 2mm on the pump and it does the job. I cut the sheet roughly to diameter and finished them off on my mates lathe. If you were very careful you might cut one out from sheet with adequate accuracy. You need to be fairly spot on, I think, as you may get priming problems. I hunted high and low for an off the shelf part but no luck. Phil
 
One of these would probably enable lathe-free production.
R05de5ff6dd34cb6952db5c800b1d6edb
 
@PTB Thanks for the information, I'd obtained details of the 'o' ring from this discussion.
I'll probably need to measure the disk in mine unless someone comes along and posts the dimensions for the disk for a MD2020 pump ...

The cost of getting some of these bearings laser cut is not that expensive, even at low volume, from off-the-shelf stock of 1.5mm and 0.8mm thickness PTFE stock.
 
Hi John, the correct thickness is important. Having made a few discs now, I do think Penfolds idea will work fine if you can source that little cutting gadget. The 2mm PTFE sheet on ebay is cheap. Good luck P
 
@PTB Yes, I can see lot's of uses for the Ratchet Compass Cutter that @penfold identified.
Yet another tool to add to the collection!

I wonder how critical the PTFE thickness is. Looking around the figures mentioned seem to be 2.2mm or 2.3mm, which is why I was thinking of using 1.5mm and 0.8mm together.
 
No they are not all the same. As mentioned in other threads I have had a batch made up for me and because of minimum amounts of sheet material I have too many. Happy to supply at a bit over cost (any surplus going to charity). The ptfe is 4cm across, centre hole is 11mm and the thickness is about 2mm. I also have the bronze discs to match. If this is a size match do come back to me
 
Personally, I wouldn’t bother trying to salvage the Speedseal arrangement. I’ve had two engines in which I fitted Speedseals and in both instances they wore more quickly than the original design configuration. I finished up removing them and reverting to the original cover plate and gasket. In my opinion the Speedseal was an attempt to cure a problem which never really existed in the first place. The only parts of the kit that were better than on the original pump were the knurled thumbscrews. Just my opinion.
Mike.
 
mikegunn said:
Personally, I wouldn’t bother trying to salvage the Speedseal arrangement. I’ve had two engines in which I fitted Speedseals and in both instances they wore more quickly than the original design configuration. I finished up removing them and reverting to the original cover plate and gasket. In my opinion the Speedseal was an attempt to cure a problem which never really existed in the first place. The only parts of the kit that were better than on the original pump were the knurled thumbscrews. Just my opinion.
Mike.
Click to expand...
We are talking about speed seal life where the benefit is the ability to run dry for a time without burning up the impeller. Useful if the inlet gets weed in it or the like
 
mikegunn said:
Personally, I wouldn’t bother trying to salvage the Speedseal arrangement. I’ve had two engines in which I fitted Speedseals and in both instances they wore more quickly than the original design configuration. I finished up removing them and reverting to the original cover plate and gasket. In my opinion the Speedseal was an attempt to cure a problem which never really existed in the first place. The only parts of the kit that were better than on the original pump were the knurled thumbscrews. Just my opinion.
Mike.
Click to expand...
Invaluable in some situations such as a Yanmar 1GM where one of the screws is almost impossible to reach. also avoids losing screws - there are 5 or 6 little 4mm ones on some pumps when access is poor. The sort of hours most yachts do (100-150 a year typically) wear is not a big issue and more than offset by ease of use.
 
I can't understand why someone else has not taken up the manufacture and marketing of this clever and useful product. The originator might be persuaded to take payment of royalties or a lump sum for the intellectual property involved, to provide him with a modest addition to his pension.
 
stuartwineberg said:
We are talking about speed seal life where the benefit is the ability to run dry for a time without burning up the impeller. Useful if the inlet gets weed in it or the like
Click to expand...
In my experience, if that was a design intent it failed. I don’t know for how long my pump was running dry because the first indication was the engine’s over temperature alarm sounding. It was caused by some plastic sheeting wrapping itself around the saildrive leg. It wasn’t the face of the impeller that suffered but the lobes on the tips of the vanes. Eventually I installed a flow switch in the seawater circuit which gives an instant alarm should the flow cease. I’m afraid that I still stand by my assertion that there is no benefit to a Speedseal (apart from the knurled thumbscrews), it just introduces more things which can wear out. The beauty of the Johnson flexible vane pumps is their simplicity and eminent repairability. The only parts that tend to wear are the impeller, cam plate, seals and bearings and perhaps the occasional shaft. The parts are easily obtainable and affordable. To add complexity and cost is to my mind a backward step. After all, if the Speedseal was as good as claimed, why didn’t Johnson adopt its principle?
Mike
 
mikegunn said:
In my experience, if that was a design intent it failed. I don’t know for how long my pump was running dry because the first indication was the engine’s over temperature alarm sounding. It was caused by some plastic sheeting wrapping itself around the saildrive leg. It wasn’t the face of the impeller that suffered but the lobes on the tips of the vanes. Eventually I installed a flow switch in the seawater circuit which gives an instant alarm should the flow cease. I’m afraid that I still stand by my assertion that there is no benefit to a Speedseal (apart from the knurled thumbscrews), it just introduces more things which can wear out. The beauty of the Johnson flexible vane pumps is their simplicity and eminent repairability. The only parts that tend to wear are the impeller, cam plate, seals and bearings and perhaps the occasional shaft. The parts are easily obtainable and affordable. To add complexity and cost is to my mind a backward step. After all, if the Speedseal was as good as claimed, why didn’t Johnson adopt its principle?
Mike
Click to expand...
Perhaps your raw water pump is easily accessible. For those of us whose aren’t the Speedseal is invaluable. 4 thumb screws, two of which can stay in situ, rather than 6 tiny slot headed screws which are magnetically drawn to the bilge make impeller changing on the water a viable proposition rather than a near impossible nightmare.
 
Jamie Dundee said:
Perhaps your raw water pump is easily accessible. For those of us whose aren’t the Speedseal is invaluable. 4 thumb screws, two of which can stay in situ, rather than 6 tiny slot headed screws which are magnetically drawn to the bilge make impeller changing on the water a viable proposition rather than a near impossible nightmare.
Click to expand...
You’re quite right Jamie and if you look at my previous posts the Knurled thumbscrews is the one aspect of the Speedseal that I praised. The OEM cover is easily modified with a saw and file to take advantage of the thumbscrews. I haven’t looked on line but I would be surprised if suitable knurled thumbscrews were not commercially available. If they’re not, well there’s a market possibly ripe for exploitation.
Mike
 
The OEM cover on my 3YM30 has 6 screws. The speedseal cover only uses 4 of them for the thumbscrews of which 2 remain in situ.


Pump cover .jpg
 
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