porous aluminium weld

Hi All.
Can anyone help with this problem?. I had some weld done on some cases which need to be sealed. On JS2 I used Devcon putty on top of the weld but it has lifted off, JS did mention a liquid that can be painted on and seal the metal but I've forgotten what he said.
Any suggestions will be much appreciated.

Thanks
Les2012.

I seem to remember using a loctite product many years ago, not sure of the product no. but if you look on their website I'm sure you will find it Les

Good hunting, Mike

vacuum impregnating les, there are companies that do i, a customer of mine once had a head done, it was a long time ago and i seem to recall about £50, they put it in a vacuum and draw all the air from the pours than cover with a sealant and release the vacuum and it gets drawn into he casting then hot water washed to remove excess and set the stuff inside.

Thank you Mike & Dan for your response to my post. I checked out the Loctite and it seems to come from the USA, will look further into it. The vacuum impregnation, the only company I've found in the UK is up in Lancashire, I have their number and will call on Monday for a chat.

Thanks again.

Les.

Hi les
the loctite you can try is 290 have used it in the past on leaking Cylinder heads which worked well
Robbie

Thanks Robbie, as a matter of interest did you just paint it on cold or did you heat up first?

Les2012.

Hi Robbie, just to let you know your suggestion to use Loctite 290 has proven a great success, the motor holds well when air pressure tested.

Les2012

Hi Les

Good to hear you are airtight. That Loctite 290 is really useful. Back in the 70's I used to heat the crankcases up and paint araldite on to the hot devcon. Trouble was I nearly got thrown out of my accommodation when the landlord came back and found me with my engine in his oven .

Are you planning attend Cadwell this weekend?

Hello Peter my old mate,
Good to know your are still interested in the Bantam, when are you going to write to me with the plans for my next engine project like what you promised?.
I well remember when you got chucked out of a flat after the landlord found a Bantam engine in his bath checking for air leaks, them were the days.

I have taken my Bantam out of service for the time being, needed to reassess where I'm going with it so no I'll not be there.

My son Kevin has bought a Honda NSR 250 mc28sp to play with so he's happy
spending loads of money, must say it looks the biz.

Hope to see you next season all being well.

Les.

Hi Peter & les.
Wish I could have got over to Blighty...
Had to miss England trip for same reason as last year: Irmy had an eye-injection last Thursday and tomorrow its another eye-doctor appointment to see what the injection might have -- or have not -- done. She needs my company although the eye-jab seems to bother me more than her...

Bantam engine in the bath? -- now I hAVE HEARD EVERYTHING ...

Did i ever tell you of Joey -- the kids budgerigar -- dying of toxic fumes in our kitchen? that was whilst their Mum and they were out and I was repairing my fibre-glass tank with the oven on full and degreaser in the fibre-glass split. I´d forgotten Joey´s cage had been put up above the hanger rail for safety away from their pet cat. I was working in the garage and forgot about the oven and when I returned Joey was on his back with his spindly legs uppermost. I´d heard that canaries sometimes recover heart-attacks by being given sniffs of cognac. I only had Glen-Fiddick so I tried that which didn´t work but had me considerably whoozy yet somewhat more brave for when all three returned. I told the truth: Joey had died of a heart-attack and I´d been so grieved about it I´d had to have a drink.
We had a burial service at the bottom of the garden which was attended by the cat. A wake followed where their Mum also got into the Glen Fiddick and asked why the kitchen neon light´s plastic cover was sort hanging down as if it had gone soft!

If you go to Cadwell I hope you hav3e a good day with warm weather -- I think I have never been to a warm Cadwell...

If you see Andy would you please explain that my computer has been down -- off line -- several times in the last few months and e-Mails impossible.

Go well and keep well,
Cheers!

John-Boy

Hi John,

Sorry to hear that Irmgard has an eye issue, hope it gets sorted out.  Well, yes I did bump into the Boiler at Cadwell  There were lots of red tanked Royal Enfield GP5's knocking about, so I thought there would be a fair chance of spotting him. Unfortunately didn't read this till just now.

Liked the story with the Canary

Oh, and it was unbelievably warm, and calm at Cadwell - Tom Miller was stripped down to a boiler (there i go again) suit.

Hi Peter!
Have had enormous bother with my PC. The e-Mail particularly. Normally would have heard from The Boiler but was on-off the PC so many times its not to know when I might have missed him. I did tell him earlier in the year that because of Irmy´s eye-injections ( up to 30 something by now... 15 or 16, or more , in each) we´d not make it across to Blighty this year.... Irmy´s eye problem started about 5 years back and this degeneration cannot be stopped completely, just delayed. She had an eye-shot last week and we go again to the eye klinik tomorrow. Its like being a permanent member of a club there, seeing many of the old fogies lining up for the jabs as if old buddies.

Bill Lawrence wrote at the weekend. Do you remember Bill as a stalwart Bantam Eastern Centre member? Later he was riding Wobbleyman´s bígger P&Ms -- He & wife did a Swis into Austria road-run just recently making me wretchedly jealous. About ten of them hire bikes and a rescue van that goes along with them.

Has Andy got his twin Alpha running yet? Got to give him credit for carrying on -- must cost a fortune what he is doing!

Re the perishin´PC -- I had the local computer dealer on my back about going for Windows 7 -- or even Windows 8 because Microsoft have withdrawn support of Windows XP. I didn´t like to tell him that part of my computer is still Windows 94 -- Sort of nearly as old as me.

Cadwell has fond memories for me. Won the Bantam Novice race there with a wrecked clutch at the top of the hill, fortunately on the last lap -- just a couple more of gdear changes before the finish. I also participated and finished two races there with my 1927 Triumph 500cc -- with hand change -- about mid-field. The hill was again the bother with the gears jumping out of mesh yet I had the fun of passing several different British makes before they passed me back -- and so on...

The back end of the triumph was solid so I´ve often wondered why there haven´t been solid back-end Bantams being raced. I´ve always felt that a solid back-end was more favourable but that´s probably only a myth of my imagination. Save money and a bit of weight ....?

Hope you are keeping well,

Cheers!

JayBee...

 


having trouble getting this to seal up also. seems that most of the leaks are from around the welding of the alloy blocks i had welded on  to form the base on which to fit the barrel. i have, internally, an open space made up of the old crankcase walls and a newer smaller crankcase  chamber for the smaller crank fitted inside , im hoping  to use this space to flow water through for crankcase water cooling. seems this area has sealed up ok, just the welds. had been thinking of some kind of sealer or paint type based system to cover the internal faces within the crankcases to aid the sealing.. any ideas? obviously needs to be heat and fuel resistant.

Nigel,
I do know of one instance which replicates your problem, namely leaky case welds. The, garden shed, remedy was viscous super glue. The interior was masked where the cyano was not needed and using similar pressurising kit as you show, the glue was pumped in. The hope was that all the leaks, nooks and crannies were pressure filled internally. I can`t recall the Loctite grade used but it had high evaporation and flash points, as the case gets hot, but as you intend to water-cool it then temps should be kept constant enough to not adversely affect the glue bond. As the internals are constantly washed with cooling mixture fresh from atmosphere, it should work. He also dribbled the cyano over all of the external leak areas as a back up! The leaks were filled, but I have no idea if it was fully permanent or not, as I lost contact with John when I re-located to Somerset. Its a long time ago and some recollections are a bit hazy now and I didn`t actually witness the event!

May be worth considering, or something similar, if only as a last resort?

Trevor

Ok, thanks Trevor, looks like everyone's in agreement on this thread.Derek has let me know also that the loctite remedy is the accepted way to go. Though maybe the engine heat cycles would make it a quick fix only way..had a go with jb weld seems to have plugged a few holes
.just the cvt to bolt on next.��

Hello Nigel, is. The engine in the picture just a bit of fun? Or trying ideas etc

Hi Dan, the crankcase set up allows me to try different barrels by changing the adapter plate you can see just below the barrel. obviously if turned up with this at a vmcc bsa bantam race meeting i wouldnt be able to score points , unless i carved off all the water jacket and had a btw barrel sweated over it ... i have some cvt stuff id like to try and cobble on to it as well, which again doesnt comply. Gives me something to play with.. originally looking to use the rotax barrel as some thing to get ideas from for a water cooled bantam barrel but while im in the mood im going to try to at least fire it up

It would be interesting to see how that set-up copes with only three gears!

If anyone wants(??) my opinion I think it is quite fascinating and I hope it doesn´t just go and vanish from the scene like so many worthy ventures ...

Cheers!

The hidden purpose behind Nigel`s Bantax, or perhaps Rotam, is CVT ??

Got down to sealing most of the air leaks only to find quite a bit of distortion, i had to have the cases barrel area re- faced. i had brazed the inner crank case with alloy rods, looks like it caused a fair bit of distortion which i couldnt seal even with trying 4/5 different sealing compounds. so just picked up the cases and ready hopefully for another go at getting it to seal for pressure test

Fingers crossed for you Nigel! You deserve a little good luck as reward for all the persistent hard work you have applied to this fascinating project.

Trevor

here we go again....



had the cases refaced due to warpage, made a new base plate to suit and fitted the cagive gp 125 barrel instead of the aprilia junior kart barrel. mainly because my crank stroke is 50.6, same as the 31bhp cagiva mito gp engine. taken it real steady... crank case pressure test tomorrow. giving the gasket sealant plenty of time to set.

Looking very nice Nigel, lot of good work there, hope the whole engine is tight! Fingers still crossed for you!

Trevor

well, got a small leak  around the out side of the small timing side oil seal... ive tried to post picture but i cant load it ... ...so ive attached the hoover to the pipe which held the pressure guage in an attempt to pull some loctite 290 into the pin head leaks. im not too disappointed, because at least everything else seems ok. not sure how long it will take for the locktite to go off, or if it will work. previously i used araldite and warmed it up with a heat gun which made the glue runny and it filled the small holes really well, so have a plan B.

i think the picture @ 600  kb is probably too large, but i dont know how to reduce it at the moment... but ill have a go...