COOT Amphibious ATV restoration

[knighty]

is the rubbish steering / wanting to go in a straight ling not because it has no diffs? all the wheels turning the same speed makes it want to go in a straight line?

for the duff worm drive the drive/input shaft looks ok, I'm guessing the cog underneath has worn away? - I've had worm drive gearboxes like that on mincers do the same... normally because of a duff bering throwing the drive shaft out of line. mine have all been phosphor bronze, £700 a time to have one made :-o

 

[CompoSimmonite]

ok finally gonna start the restoration on this thing and may need help/advice as after 50years its got a few 'issues' to say the least. Hopefully start the strip down this weekend just need to clear a bit more room in the workshop plus looks like i may have another to do as my friend has sold his one and wants me to restore it for the buyer at the same time.
First thing i need to do once the hulls are stripped out is to separate them and get them to the sand blaster is it worth me cutting out the rot first or just let it end up on there floor?
The biggest problem i have is one of the gears in the back axle is screwed and i need to get one made any ideas picture below

View attachment 166853

IMO best to leave cutting out rot until after sandblasted and you can properly assess what needs repairing

 

[armalites]

The biggest problem i have is one of the gears in the back axle is screwed and i need to get one made any ideas picture below

View attachment 166853

I spoke to these guys a few years back and they seemed pretty good.

https://www.hewitt-topham.co.uk/

 

[dieselsamurai]

is the rubbish steering / wanting to go in a straight ling not because it has no diffs? all the wheels turning the same speed makes it want to go in a straight line?

for the duff worm drive the drive/input shaft looks ok, I'm guessing the cog underneath has worn away? - I've had worm drive gearboxes like that on mincers do the same... normally because of a duff bering throwing the drive shaft out of line. mine have all been phosphor bronze, £700 a time to have one made :-o

All wheels are driven at the same time the worm drive bevel boxes give it much higher ground clearance but mean it can only be driven off road otherwise lots of stress in drive train, 4 wheel steer should make it easier to get out of ruts etc

Sorry should of said thats not my one i'll take a pic of it later it was left in the hull as bearings went before i bought it . Was very rusty and cant see it being usable now

 

[dieselsamurai]

I spoke to these guys a few years back and they seemed pretty good.

https://www.hewitt-topham.co.uk/

Great they look promising , I think there are a few engineering firms near me i might see what they think too

 

[chris pruteanu]

Ill take some photos of drive etc tonight if i can , i think i have a couple of pumps somewhere so having a pedal that combines forward and reverse maybe appeals

its going to be a long term project but i hope to split the hulls in the next week or two so my argocat can live in the car port for a while

a little 10hp diesel should be good even with the old drive train

Look for microcar lombardini engines, diesel, 2 cyl and 16 bhp water cooled engine which has a variator/varistor to go 2 wheel drive but i am sure a 4 wheel drive system can be implemented as well. Some italian goldini tractors have a 4wd system that bolts to a lombardini engine... Quite easy to retrofit and the engine os self contained with all bits...

 

[bricol]

Great they look promising , I think there are a few engineering firms near me i might see what they think too

Hewitt and Topham, who used to be in Keighley, were bought by Renown Gears a few years ago. I'm working with Renown / being educated on gears/profiles/materials on a fairly major project involving Newcastle Uni Design Unit Gear Technology and the government, and they know their stuff! They are gear people with massive knowledge, who happen to also make some general engineering stuff, rather than the other way around. If they don't know, I reckon it can't be done .

 

[Migmac]

looks a fun wee machine.

 

[dieselsamurai]

Hewitt and Topham, who used to be in Keighley, were bought by Renown Gears a few years ago. I'm working with Renown / being educated on gears/profiles/materials on a fairly major project involving Newcastle Uni Design Unit Gear Technology and the government, and they know their stuff! They are gear people with massive knowledge, who happen to also make some general engineering stuff, rather than the other way around. If they don't know, I reckon it can't be done .

Im hopefull it can be done otherwise the project stalls at first hurdle tbh, the other one i need to restore has ok gears i believe but its mine i want to get done too. There is a guy in the USA that makes replacements but not cheap

 

[dieselsamurai]

this is my worm gear looks fudged to me

 

[knighty]

that looks fine to me... those bits are hardened... it's the gear is meshes with that takes all the wear and tare / any damage

 

[dieselsamurai]

that looks fine to me... those bits are hardened... it's the gear is meshes with that takes all the wear and tare / any damage

Really you think the divots wont matter ? if thats the case im a happy chappy

I really dont want to damage the gear it meshes with as thats the expensive one , mine looks ok they are £350 to get a replacement

made from bronze

 

[knighty]

give it a good clean up and see what it looks like.... as long as there's no sharp bits to scrape/grind the other gear I'd still use it

plenty of oil in the gearbox when you fill it.... I always put in more than the fill level - the ones I've worked with are made for splash lubrication, the bottom edge of the big gear is only just in the oil level so as it spins it scoops up oil and spreads it around... oil level is set so it only just picks up a little bit.... I'd rather lose a fraction of efficiency and have plenty of oil in, to me it's better than the change of running low on oil, and it makes sure plenty is splashed over the bearings etc. too


EDIT: looked at the photos again, I think if you have a wire wheels on a grinder or drill it'll clean most of that up good as new

 

[dieselsamurai]

give it a good clean up and see what it looks like.... as long as there's no sharp bits to scrape/grind the other gear I'd still use it

plenty of oil in the gearbox when you fill it.... I always put in more than the fill level - the ones I've worked with are made for splash lubrication, the bottom edge of the big gear is only just in the oil level so as it spins it scoops up oil and spreads it around... oil level is set so it only just picks up a little bit.... I'd rather lose a fraction of efficiency and have plenty of oil in, to me it's better than the change of running low on oil, and it makes sure plenty is splashed over the bearings etc. too


EDIT: looked at the photos again, I think if you have a wire wheels on a grinder or drill it'll clean most of that up good as new

Cheers for advice , i will try to get a better picture later as to me it feels really rough but like you say if i can make it smooth oil will do its job

 

[bricol]

I have to say, unless it's the lighting, that gear, hardened or not, looks knackered! Not worn maybe, but rust, pitted, corroded. If it is, it will cause vastly accelerated wear on the other - which looks to be the sacrificial one anyway. Attempting to smooth it out will bugger up the tooth profile even more, and cause more issues.

Yes, it's run and drive, but . . .

With a few measurements, you should be able to work out what DP that is, whether it's corrected or not, and get some idea of the cost of a replacement.

 

[dieselsamurai]

I have to say, unless it's the lighting, that gear, hardened or not, looks knackered! Not worn maybe, but rust, pitted, corroded. If it is, it will cause vastly accelerated wear on the other - which looks to be the sacrificial one anyway. Attempting to smooth it out will ****** up the tooth profile even more, and cause more issues.

Yes, it's run and drive, but . . .

With a few measurements, you should be able to work out what DP that is, whether it's corrected or not, and get some idea of the cost of a replacement.

I will try to take a better photo as i think the ones above make it look better than it is , funnily enough its mostly the steel gear not the bronze one that wears much like on a rover v8 were the alloy rockers wear out the steel shaft ( a common fault). Spoke to my friend today can hopefully get one made if the other one is good enough to copy

 

[Pigeon_Droppings2]

Guess it's a bit like small tyres on cars wearing out quicker....the smaller gear is doing many more rotations I think for each rotation of the larger gear so maybe thats why it wears quicker?

 

[dieselsamurai]

Guess it's a bit like small tyres on cars wearing out quicker....the smaller gear is doing many more rotations I think for each rotation of the larger gear so maybe thats why it wears quicker?

yeah the axles are 18:1 so i guess thats part of the reason it wears the bronze gear less

 

[dieselsamurai]

Not a toy

 

[HopefullySoon]

Depends on your definition of toy .