Must be my old age,or have i got ‘PUCHITUS’ but i have succumbed to temptation and have brought another Puch a 175SV in need of TLC the description said the Puch is seized through standing(we will see?) once the bike was on my ramp a very quick inspection showed some damage caused by going about trying to use brute strength to free the pistons.In the past i have been able to free at least 4 ~Puch’s 250 175 and 125’s by useing a hydraulic press but to do that you have to split the motor down to a crankshaft and barrel.You will not do it by Hitting the piston with a wooden block via a hammer or worse still trying to put a lot of pressure on the kick starter !The result will be mechanical damage as can be seen in the photo’s below!! The previous owner put so much pressure the kick starter that the primary chain broke!! I am amazed that the kickstarter splines didn’t go first, so i will hopefully show the correct way to do it with photo’s in the near future.
The Puch 175SV was never available to buy on the UK Market it differs from the 175SVS in only having 1 carburettor it gave 10BHP compared to the SVS 11.5 BHP this bike came from France and is in the very popular colour of light green.
Footnote. any viewers of this article have any puch 175 SVS parts in the UK they want to sell let me know berniesmotorrad~at~gmail.com
It’s now 2 days later from the above photo’s and after being confident of freeing the seized pistons the task is becoming more difficult. Good points first, i have found the crankshaft will rotate this is done by undoing the barrel base nuts,detaching the exhaust pipes and then rotating the crankshaft if it lifts the barrel you know the crank,bigend haven’t seized. Now if you are lucky the barrel will lift up over to top of the base stubs which means you can take the motor apart just leaving the barrel,crankshaft and piston separate from the motor!!Bad news the pistons are just below TDC which means the barrel will not lift enough to clear the stubs also as can be seen in the photo’s the muck and corrosion is quite severe !! as said the selling description seized through standing is very true !it looks like mushrooms may have been growing in the combustion chamber!!
Next day, engine out and on my work bench! When the engine was turned on it’s side out poured lots of rusty coloured water, one sight i didn’t want to see,if a engine has a residue of oil in the crankcase,gearbox or primary chaincase parts tend not to corrode or seize through rust.You do not want to see water Bad news! and then more bad news looking at the first pictures the tank looked O K! no dents,no rust but today the tank came off! and one side at the bottom was kapput wafer thin metal ,no metal and holes ,the reality is the tank is knackered so a search is on for a tank.UPDATE …a few hours later one has been seen on Austrian ebay lets hope i am top bidder!!
Over the weekend i have had the puch engine under a hydraulic press with about 5 tons of pressure on the pistons but i have to admit to failing to freeing them up! So the next step is a drastic one of destroying the pistons at least they are available,so with a few heavy hits with a sledge hammer (did i say nether do that!!) i manage to get the barrel above the base stubs and split the engine also more drastic action i also had to saw the conrods(i have a spare crank) to separate the barrel from the crank the resulting pics will show why i did not succeed in freeing up the pistons as said earlier the sign of water in the engine is always bad news The barrel bores are severely corroded and the barrel is already at maximum bore size so its a write off!! with this restoration game you have good days and bad! TODAY IS A BAD!BAD DAY!
Anyone in the UK has a barrel for a Puch 175 SVS or SV let me know
Hello again its now August and in between riding and getting bikes reading for runs etc, i have given some time to the Puch SV engine, Having got a Barrel bore out to 44mm and some pistons its time for the bearings and seals these came from RBO so i set about getting rid of the old ones all came out after putting crankcases in the oven 10 minutes at 180 degrees only one problem is that the gearshaft bearing release is blocked by the speedo drive shaft which is held in place by a tight bronze bush i came up with a solution of a 4 inch (100mm)carpenters G clamp with the end ground away in a U shape so that it’s a nice fit around the bottom of the shaft.
NOW FOR THE BIG MYSTERY!?!?
Once all the bearings were removed i set about cleaning bearing surfaces and oilways! The oilway for the inside driveside bearing was blocked with what i first thought as being a broken drive bit (when the engine is made a 6mm hole is drilled from the outside of the crankcase 6 inches through the bearing holding surfice to reach the oil gully. Now the Bearings have to in place for the engine to be assembled so how can 2 small pieces of piston ring end up being in the hole???)
It’s now November 2017 and the SV is progressing the motor has been refurbished ie new barrel ,pistons and crankshaft and the bike has been stripped and cleaned it was never going to be a restoration but more of a case of getting it up and running! apart from rewiring the only other job is the front forks.I knew things were not right with the forks! when the Puch was on it’s stand the forks dropped far beyond the correct level so much so that i could see the fork steel tubes!! so on stripping down the forks i came across More Trouble!! i think the pictures below will describe the damage! so a new set of Springs/Forks is called for.