I mentioned in another thread I had recently acquired my parter's Grandad's Rover Thoroughbred 16". It has been sitting for years, and I'm gonna have a go at resurrecting it and thought I'd start a thread in case anyone else can benefit from it. As I say , it had been sitting for at least 5 years in a shed up on the border of Victoria, maybe more. It had a lot of crud in all the mechanical parts, so I thought I'd clean up all the drive assembly first before I stated on the engine. These have a centrifugal clutch, so the last thing I wanted was to start it up and have the reel scraping all over the place. I might add, I've never had a cylinder mower but have wanted one for ages,I use a Masport Cleveland push mower mostly, because I hate the cut a rotary give, so I'll be learning as I go.
So I spent a rainy day in Melbourne taking the chain off a soaking them in petrol, then scrubbing them with a toothbrush and re-lubing with Penrite chain oil. Worth thinking about where the overspray will go, because it's sticky and you'll cover your freshly cleaned frame. I had also noticed that as I adjusted the reel lower to get a good setting to the bed knife, the reel to intermediate drive chain became really tight , so I took the opportunity to set the reel where I wanted it, then adjust the chain tension. Took a bit of fiddling because you move up and down and back and forth at the same time. There's a great video on facebook of how to do a Scott Bonnar 45, and this is the same way.
So now the drive assembly was done, I cleaned the reel, sprayed it with WD40 and let it sit, then scraped it off with a thin paint scraper followed by a wire brush. There was actually still some red paint under there. I took out the sole plate, because there was all sorts of gunk scraping against the reel, gave it a scrub then a little wet and dry just to take the surface rust off. So it was all spinning smoothly now except for one little thing, which I'll get to next, and it drove me nuts trying to work it out. As well as that I found that the bottom blade had about a 1cm chip out of the corner at the left end, which is a total drag, but I'll deal with that down the road if I can find someone to fabricate me a new bottom blade. I mean, how hard can it be?
The two bolt pictured here are what drove me nuts. When i pulled the sole plate, i didn't think anything of it, but two of the bolts were shorter. After i put it back and adjusted the reel I couldn't get the right end of the reel to brush the bottom blade, the reel blades kept catching against the inside curve of the sole plate when they were moving at the back of the reel. I thought about it all last night, was the bearing housing pulled forward by the tension of the intermediate chain when I lowered the reel? I had a look and not possible. So this morning I decided I will replace all the bolts for the sole plate. Looked up the part, and it doesn't match. i think my model is earlier than the one on here. took one of the long bolts to Bunnings and tried the thread sizer there, it was 5/16 x 3/4". Grabbed a pack, got home, they don't fit. I bought UNF thread, must need UNC. We have a local hardware as well so went there, found the uNC and came home. They don't fit either! Whaaat is going on. Went back to the bolts that were in there, and notice they had the tiniest bit of play in them, like 1mm. the sole plate has a tiny bow in it, so I pushed it back wards as hard as I could and locked off the long bolt on the right side. This worked, and i had clearance now, the reel was lightly brushing the bottom blade without hitting the frame. I gave it a back lap and the grind was even, much better. It needs a sharpen, but this will do till I get it all running.
With the drive section all good and the sole plate issue conquered, there was one more issue with the mechanical side. The drive clutch that runs the rear roller self drive was engaging, but not disengaging. While i had the chains off I had pulled apart the large intermediate sprocket to see if the cork was sticky, it wasn't and was actually in really good condition. In the centre is the clutch operating bolt that squeezes the sprocket on to the cork. If that bolt is too tight, the clutch stays on the whole time. It wasn't too tight.
I didn't take a pic, so I borrowed one of an SB45, they are really similar in the drive assembly, but if you take that bolt in that last pic out, the orange bearing sits on a sleeve that has a pin in the inside of it. This pin sits in a slot in the shaft (pictured) and makes the bearing spin. I had heard from a guy on the Scott Bonnar Restoration FV page that he had found some notches in the slot on his, and the pin was catching on them so he gave it a light file. I looked mine over with a magnifying glass, and that wan't the problem either. That's a really helpful resource as well as here, as the Thoroughbreds use a lot of the same principles as the Scott bonnar 45's.
So finally I found it. The clutch operating lever that the clutch cable attaches to pulls the clutch bolt in and out. Mine was going all over the place when you squeezed the clutch handle, and the wiggling side to side was causing the clutch bolt to get trapped in the hole in the lever, so it couldn't release. I decided the spring was too tight and forcing it all over the place. I was wrong. It was too loose, so twisting the hex casing on the end of the cable on the left of the pic firmed up the spring and the clutch operating lever now went straight back and forth. I wish iI'd checked that before I pulled all the other stuff apart trying to find the cause. The simplest cause is usually the cause..
I'm happy enough with where I've got all the mechs for now so on to the other half, Briggs and Stratton model 91202 0059 01 , made in July 1992.
First up are to drain the oil, which looks like treacle and fix the stuck throttle on the handlebars. I spent ages trying to find the manual, but the model on the 91202 manual looks nothing like mine. The oil drain looked like a square key rather than a bolt. I spent ages trying to find one, and it turns out it is actually a hex key, just had grease in it that made it look square. So the oil is draining overnight, and I've taken the the throttle cable off and lubed it then hung it for the night so hopefully some lube will work it's way down inside the casing.
Picked up a new air filter, still available after 30 years, new plug and had oil, so tomorrow will get it all in and see if it starts..
OK, so it's not starting...haha..Merry Christmas! I'm not really surprised considering it's been sitting for so long, but I had to give it a go. Tipped some petrol into the cylinder and it fired, just didn't keep running, so it's not getting fuel. Exhaust isn't blocked..Carby will come off and get a clean, new diaphragm and gaskets. Nobody local has them, so will have to order online, which is gonna be slow this time of year. Oh well, if anything this project is teaching me patience..
Well that's the carby out. That was a learning experience. It was stuck to the block good, but eventually it came loose. Giant blob of furry hairy stuff in the fuel tank blocking the intake screen.. but a bit of debris in there so have flushed the tank and ordered the gasket etc. Will give it a clean on boxing day or the day after.
Carby is clean, waiting on new fuel diaphragm and tank gasket, just got notice they were posted today. In the process found a split crankcase breather tube grommet and am still looking for a replacement. Only online store I found in Aus will cost me close to 30 bucks including shipping, which is um pricey.. Also found oil in the breather tube so pulled the breather assembly and looks like it's been tipped at some point. Cleaned the breather by agitating it in petrol and it is flapping fine now, so just need to find the best way to clean the valve chamber.
As I can't put it all back together because of waiting on parts, I decided this morning to strip the deflector. Half the paint is gone off the face the grass hits and there's surface rust. I may strip the whole mower down and repaint the deck at some point, but I just for now want to halt the deflector getting any rustier. It actually was pretty low fuss, just used paint stripper, gave it a going over with a wire brush, then a second coat of stripper and fine steel wool. All came off and now it is soaking in a vinegar bath to remove the surface rust. Supermarket girl looked at me a bit strangely buying 12 litres of vinegar. Said I really liked chips.
Gave the deflector a spray today in metalshield hammer finish blue. Doesn't quite match the original colour which has more green in the colour mix, but that's rattle cans. At least the surface rust is gone and it will see out this summer till I decide if I want to do a total strip down ad respray. This was back to bare, etch primer then 4 thinnish coats.
Meh.. with the boredom of waiting for parts in the mail, I cleaned the rust off the chain cover and treated the metal, then patch a small hole that was down the bottom. Looked like someone had cut it out for easy lubing of the reel chain..odd..just used the blue hammer finish I got for the deflector. It's nowhere near the original but it'll do for now to keep the rust at bay. I also sprayed the shroud and heat shield with engine paint and did the tank and airbox while I had the carby off just because..well.. I was bored. So bored I also gave the front roller a vinegar bath and a scrub with steel wool to removes the surface rust. On positive news the new diaphragm and gaskets arrived in the mail today. Got a bit of work on tomorrow so hopefully will have it all back together Friday and see if it starts or not.
Todays job got postponed so I bit the bullet, put it all back together and had a crack. Couldn't get it to start at first even with priming the carby, but backing the choke off did the trick, and it's alive. Running pretty good. Reel needs a sharpen, but for now I'm just happy I got it all back together and it works.
Benn running it a few times, all going good engine wise. Can't keep going without a reel sharpen, so I found a guy who will do it for me out of the mower, as I don't have a car the whole mower will fit in. Reel is out thanks to advice from here, and my next door neighbour is making me a new bottom blade in the next day or so at his steel company. I'll drop them both off for a sharpen early next week, then give the reel a respray and put it all back in. Back to the Masport push reel for me for now.
So it's had a respray, reel grind, new bedknife and it's just about mowing again. Just waiting on a woodruff key for the reel sprocket as I found it was broken when I took the reel out. Catcher matches now, forgot to take a pic.
