Very old Briggs and Stratton

Really been cracking on today. I cut myself a new head gasket, I just hope it's up to the job (I believe this stuff is good for water cooled head gaskets, not sure about air cooled, it should be fine though)....



The Kurust on the barrel was dry, so I gave it a quick hone before masking off the top, bottom & other holes & spraying a couple of good coats of high-temp black (BBQ paint). It says to bake it on within 8 hours, but that won't be possible, so I will just have to take my chances (again, should be fine).

I replaced the oil drain plugs & put a litre of oil into the sump. I turned it over a few times & the pump is working. Only a dribble really, but I guess it's enough? It should amount to a good squirt when it's running, I suppose.

While the barrel was drying I cleaned up the head as best I could. It will still need painting silver at a later date, unless I can get it blasted or cleaned some other way (maybe cavitation cleaning or that sonic cleaning? I would rather it wasn't painted, I always think silver painted ally heads look a bit naff).
Anyway, once the barrel was dry I glossed the inlet tube & set about re-fitting the valves. I only gave them a quick grind, as they didn't look too bad. Once they were re-fitted with springs & stuff I decided it was time to get the barrel re-fitted....



Then came the valve clearances. I've no idea what they should be, so I set them to a slightly loose .010". They must be the most awkward valve clearances to adjust, especially when half the stuff in the way is covered with wet paint!
But eventually they were done, I replaced the cover (forgetting to give it all a squirt of oil in there, must remember to do that before I start her up) & put the head back on.

Then came the carb & governor arm. This was another PITA job! But after I worked out which way round everything went I had it back on....



On went the cowlings, & the breather tube, & here I am....









I've been playing around with where the fuel tank & HT lead are going to go, & haven't made up my mind yet. Next I need to get some more oil, get some fuel & strap it to my engine test bed (which has a fuel tank attached) for a test run.

I will fit the fuel tank at some later date, it will require some new fittings fabricating.

All looking good Nuts, can't wait till Thursday till it gets it's test run to see how she runs.

Stu.

Right, I have finally got this one running! I first started it yesterday (Wednesday) afternoon, but it wasn't all plain sailing....

After a lot of rope pulling I was getting nowhere. I decided there had to be something wrong with the timing, as all I was getting was the occasional pop back through the carb (maybe something to do with the idle spark on these engines?).

So, off came the cowlings, off came the flywheel & off came the head. I checked the valve timing, & it's fine, I then checked the ignition timing & I wasn't happy with it. Thankfully, that very morning I had received an email with a copy of the "Briggs & Stratton Tune Up manual" which covered this engine. I had been reading it all morning, & I remembered reading that you could fine adjust the ignition timing by re-profiling the chamfer on the points arm pad thingy (that's a technical term, don't ya know). So I checked it & it did seem a bit worn, so I had a go at re-profiling it. It seemed to advance the ignition very slightly, but of course I had to re-gap the points as well. I just wish I had the proper Briggs tool to check it with. It seems very well retarded to me, the timing on these.

Well, I put it all back together & pulled it over a few more times. the carb seems to do nothing but drip fuel, so I was sure it was getting through, but still couldn't start it.

So I walked the dogs for half an hour or so, came back, pulled it again, still nothing, so I did it again & she fired! But stopped the moment I opened the choke. So i gave the needle a half turn outwards & pulled again & she went!

I must say it's a bit rough. I think the carb's pretty worn out, it doesn't like sudden throttle changes & is difficult to find a good setting on the needle, so maybe I should strip the carb down again & see if there's anything wrong.

But, once you find a certain setting on the carb, & a certain setting on the governor spring, she plods along quite nicely. She's a proper "thumper" as well. You can tell it's a long stroke engine, you can feel it thumping away through the ground under your feet, & she doesn't like being run on hard concrete.

I went back that evening & re-set the valve clearances, as I had seen from the Tune-Up manual that I had set them wrong. They are now both spot on. I also noticed the lubrication system is working very well. I hadn't put any oil in the valve spring area, & there's only a small hole from the bottom of the barrel through to there, but there was plenty of oil in there when I took the cover off, even after just a short run.

Right, here's some pics of her on my home made engine test-bed, with integral fuel tank (she'll stay on this until I fabricate some mounts for the new tank)....









There's more pics on the album as well....

[URL="http://photobucket.com/nutgonesbriggs"]http://photobucket.com/nutgonesbriggs[/URL]

I will leave the final painting until the weather warms up a bit. Next I've got to sort out some tank mounts & something more permanent to fix it to. We won't be putting this one on a wheeled trolley. Although she's quite heavy (I can just about lift her, but it's more awkward than anything) I don't think it would suit a trolley. I think Ian & me are thinking something along the lines of a wooden frame, with stretcher style handles. More "skid" mounted.

I will get a video of her on the weekend & stick it on my YouTube channel.

I'm sure you'll soon get the fine tuning done so it will be purring along.

Looking forward to seeing the video,

Stu.

I was over there last night and to me she sounded fine. Yes the carb does need some fine tuning but I reckon I can manage that. Sorting the leaking problem out would be useful as well but it didn't seem to leak while it was running.
It did sound as if she was getting a little fuel starvation sometimes but I blame that on the tank set-up on that test bed and the horrible fuel pipe union on the carb. We need one of the proper square, brass unions on it and some proper decent copper fuel pipe.
Still, at least we know she runs and she was running rather nicely when I was there. I'll get my rev counter on her soon and see what sort of revs she likes to run at. I'm guessing she was doing about 1200 when I saw her, much slower and she started to run a bit lumpy. This engine was designed to run at between 1800 and 2400rpm but I'd be happier to keep her a bit lower than that, as long as she's happy to run at the lower speed. We will find a happy balance I am sure.

The carb does give the occasional drip when running, it's definitely worn, but it works well enough.

I will need to spray that side of the crank case with petrol proof lacquer, as it's taken the paint off a little down there.

I ordered some of the correct decal transfers from America today. These particular decals were only used from around 1929 until early 1932. The guy only had 2 left, so I got them both. they should look good when they eventually make it on there....



The cowls on our engine are bigger than the one in the picture, so these decals won't go over the edges on ours.

I do like them decals they will set the engine of nicely, I can't remember ever seeing any like that before, well found nuts.

Stu.

So, Ian came over, with his eldest son (a young budding enthusiast) & we dragged this engine out to give it a bit of a run.

I took some more pics & even got a bit of a video. I will link to the video, but it's not very good. The video plays fine on my phone, but there's something going wrong with the upload to YouTube, it happened on my last one too. So I will have to plug the phone into the computer & do it that way.

Anyway, here goes....

Running great guys well done.

Nuts it's like your video is buffering as it's running, sorry no idea how to solve the problem.

Stu.

I think what's happening is I'm trying to upload it straight from my phone using the mobile internet. It keeps stopping the upload & I have to re-start it. When I re-start it it picks up where it left off. I think I either need to plug the phone into the computer & do it that way, or switch my phone onto wifi (a better connection than mobile internet) & upload that way. My old phone wouldn't let me upload videos on mobile internet, it would only do it through wifi, so maybe that should tell me something.

I'm not happy with the camera on this phone anyway, not so sure about the video, but the camera pics are all coming out too red. There's just too many settings on it. The best stuff has less settings, like stereos, the cheapo ones all had graphic equalisers, the best top notch stuff just has a volume knob, & possibly a tone function. This cheapo Samsung Galaxy phone has loads of settings on the camera, my last one just had 4; sports, macro, night & auto focus.

I might just go back to the old one.

Nutgone,

Well done job! It runs decent, but I wonder if it would like some sort of flywheel on there to smooth it out a bit, that may just be what it needs if it is to run "no-load".
In addition you may be able to tune down the rpm with a weighted crankshaft, and make it run around 5-600 rpm.

I always liked the Brigg's, they are simple and easy to work on.
I have a few 8 and ten horse ones, that just won't quit.

Tick off another one saved from the yard lol,

Regards, John.

Cheers John.

I had a little look at the Briggs tonight, when I went out for my final cigarette of the evening. It seems someone has left the fuel tap switched on, I checked in the tank (only a small tank, but I distinctly remember Ian filling it up the last time the engine was run) & it is now completely empty & all the silver paint on the top of the carb has bubbled up.

Really must sort out this fuel leak problem, I don't like my engines not being fuel tight. Most of my other engines can have the tap left on indefinitely, with little or no problems. I do usually close the taps though, but it's one of my "things", a fuel tight system (even if this engine is about a month off it's 82nd birthday, that's no excuse for incontinence!) It means that when accidents do happen & Ian forgets to close the tap ( ) that we don't end up stripping paint off our machines.

Not to mention the waste of fuel. That little mower tank must hold at least a jam jar full of petrol!

nutgone wrote:Cheers John.

I had a little look at the Briggs tonight, when I went out for my final cigarette of the evening. It seems someone has left the fuel tap switched on, I checked in the tank (only a small tank, but I distinctly remember Ian filling it up the last time the engine was run) & it is now completely empty & all the silver paint on the top of the carb has bubbled up.

Really must sort out this fuel leak problem, I don't like my engines not being fuel tight. Most of my other engines can have the tap left on indefinitely, with little or no problems. I do usually close the taps though, but it's one of my "things", a fuel tight system (even if this engine is about a month off it's 82nd birthday, that's no excuse for incontinence!) It means that when accidents do happen & Ian forgets to close the tap ( ) that we don't end up stripping paint off our machines.

Not to mention the waste of fuel. That little mower tank must hold at least a jam jar full of petrol!

The Gall of that petrol to just run out and all!!! Making you look bad like that.lol
and then to be out and smoking a fag at the same time, see how Murphy does it?

I am of the same conviction Nutt! petrol is not a good thing to have dancing around in vapor form, and a good thing it was outside
Leaks can do things that we all wish wouldn't have happened when they did.

But non the less, that's a nice engine and paint is not a big deal.
Hope you can fix your leak,

Regards, John.

What's wrong with you all? No sense of adventure

I'm not sure it was outside when it happened. I think it's all soaked into the wood that the engine is mounted on.

I think we're pretty safe in this cold weather. I even smoke when I'm using my parts wash & the little wire brushes. Nice fine mist of flammable liquid.

I'm told you can actually put a cigarette out in a bucket of petrol, & I know for a fact you can put a lit match out in diesel, because I've done it. As John says, it's the vapour that's the dangerous part, but being outside (or in a well ventilated workshop) I'm pretty safe. Most of the stuff we play with is the kind of stuff which accelerates fires, rather than starts them.

Anyway, I'll get that carb off the Briggs when I've finished cleaning the latest pile of bits from the Kohler (I'm doing the governor at the moment).

Nuts you must be devistated to have lost that much fuel, you need to sort that leak out fast before it breaks the bank

Stu.

I've been playing about with this one again over the past couple of days. I took the carb off a couple of weeks ago & have been slowly scraping all the paint off it. I realised partly why it didn't stick, because the metal was so dirty & crap. I think it really just goes to show what I've always said, "Don't paint carbs!" I've polished it up as best I can & given it a good clean out. It seems there are 2 tiny little holes for the idle jet, one just after the throttle butterfly & one actually on the butterfly, these help it go on & off idle without cutting out. Well, it seems both of them were blocked, so I cleaned them out & gave the whole carb a good once over.

I put it all back together & got her started, but she was still running very lumpy. Then Ian came round with his rev counter & she just died! I checked for a spark & there was none. After some testing I found this was the condenser. It still tested fine as a capacitor, but when tested with a Megger (insulation resistance tester) I could see that it had broken down internally.

It's an original condenser, so I pulled the guts out of it, soldered a modern capacitor in there & encapsulated it into the old case with some silicone instant gasket (ideal as it will withstand much higher temperatures & chemicals than normal silicone sealants).

I put it back together today & it's running much better, still not great but that's mainly due to the carb, it's knackered, & after 82 years who can blame it. I might have a go at building up the throttle spindle with JB Weld to see if I can make it seal better. Most of the wear seems to be on the spindle, rather than the bushes, it might improve things. I would rather add to the metal than go machining grooves for O rings or suchlike.

Anyway, the saga continues, & still I'm no further with making up some tank mounts. I think next job will be to make up the missing bit of cowl....



I will probably make it from sheet aluminium as that's what I have most of.

I'm sure you'll manage to sort out the running problem without much trouble, and as you say it's easier to build up the spindle then find bushes, even if you did it that way it's still a worn spindle and it won't be completely round.

Stu.

Yeah, I was thinking about building up the worst of the worn bits with JB Weld, then spinning it in a drill with some wet & dry abrasive paper, in the hope of getting it as round as possible.

We do have a family friend with a lathe, so I could take it there. It's been a few years since I used a lathe though. Not sure what would be correct to build up a brass shaft with. I would think solder would be too soft, so perhaps lead? I think brazing would be too hot for brass, maybe silver solder?

Anyway, I will go with the JB Weld for now. Might even do that today, if I get a chance, it takes quite a while to harden off properly.

I have got O rings which would fit the shaft, but I don't think they could be made to actually seal unless some serious machining was done, & O don't really want to do that. I might be able to do something with some silicone instant gasket though.

I'll whip the carb off again & have a look at it, see what can be done. I'm pretty sure the worn shaft is what's causing the worst of the lumpy running. I know the jets are probably worn as well, but they are adjustable & I have polished the faces of the needles on both of them as there were the usual wear grooves from over tightening. That seemed to improve things quite a bit, so hopefully some work on the throttle spindle will improve it even more. The condenser seems to have improved the running as well, that old one must have been getting pretty bad, they tend to deteriorate & break down over time, then just give up, as this one did.

nutgone wrote:Yeah, I was thinking about building up the worst of the worn bits with JB Weld, then spinning it in a drill with some wet & dry abrasive paper, in the hope of getting it as round as possible.

We do have a family friend with a lathe, so I could take it there. It's been a few years since I used a lathe though. Not sure what would be correct to build up a brass shaft with. I would think solder would be too soft, so perhaps lead? I think brazing would be too hot for brass, maybe silver solder?

Anyway, I will go with the JB Weld for now. Might even do that today, if I get a chance, it takes quite a while to harden off properly.

I have got O rings which would fit the shaft, but I don't think they could be made to actually seal unless some serious machining was done, & O don't really want to do that. I might be able to do something with some silicone instant gasket though.

I'll whip the carb off again & have a look at it, see what can be done. I'm pretty sure the worn shaft is what's causing the worst of the lumpy running. I know the jets are probably worn as well, but they are adjustable & I have polished the faces of the needles on both of them as there were the usual wear grooves from over tightening. That seemed to improve things quite a bit, so hopefully some work on the throttle spindle will improve it even more. The condenser seems to have improved the running as well, that old one must have been getting pretty bad, they tend to deteriorate & break down over time, then just give up, as this one did.

Hey Nut,

Couldn't you use a generic bit of brass round stock? Butterfly rod should be close to a standard size(1/4 or 5/16ths) no?) and whittle one up with a file? Iv'e done one and it was easier than I thought. The end holding the throttle arm gave me more trouble than making the rod as it was a square end and I had to peen it to crimp the lever on.
The threading was not possible for me at the time so I squash pinned the butterfly to the shaft out of desperation, but it was successful and still works for the man I did it for.
I don't know what tools you have but you may even have a small tap and die set that'll work.

Regards, John.

I probably could do that John. I've got quite a few taps & dies, including loads of metric stuff with screws, nuts & bolts to match. I've also got a small drill press (bench top model) & my trusty dremmel, which takes the place of a file in a lot of instances.

I don't have any suitable bar stock though (that's my main hold-up in this workshop, I have very little spare metal stock, apart from aluminium sheet & copper pipe). Also, the spindle/shaft on this one has a slot machined through it long-ways which the butterfly slots into, rather than just a flat filed into the spindle, so to get it in exactly the right place wouldn't leave a lot of metal there for strength.

I may well end up having to make one though, & to be honest I hadn't considered it until you said.

nutgone wrote:I probably could do that John. I've got quite a few taps & dies, including loads of metric stuff with screws, nuts & bolts to match. I've also got a small drill press (bench top model) & my trusty dremmel, which takes the place of a file in a lot of instances.

I don't have any suitable bar stock though (that's my main hold-up in this workshop, I have very little spare metal stock, apart from aluminium sheet & copper pipe). Also, the spindle/shaft on this one has a slot machined through it long-ways which the butterfly slots into, rather than just a flat filed into the spindle, so to get it in exactly the right place wouldn't leave a lot of metal there for strength.

I may well end up having to make one though, & to be honest I hadn't considered it until you said.

Well that's good then isn't it?

Nothing wrong with a screwdriver shaft for a spindle, but one with the flat Dremeled into it (I like filing ) , no good reason to slot a butterfly spindle in the first place, it's a waste of time and energy IMHO. Screws are better but riveted with mild steel nail as material works as good, just be more careful when hammering the rivet, done that too and it works as long as you make sure the butterfly sits centre shaft so that the bevels on the butterfly edges that touch the throttle hole walls (if it has any bevels) touch just right.
Some bevels have an idle slot, some don't and seat just off so idling can benefit, and some have a straight cut edge and others are beveled one side.

Just rattling off with some of the stuff I remember I went through.
Mind, I was one of those kind that likes to whittle and fit and jiggle round with parts filing me arse off and that has slowed somewhat as I want less time spent now too and have quicker results.
You may not be that same kind and just want to get it done and running.
The end justfies the means on some of it I say.

So all of this is just friendly chatter, Hope there's some use in it for you.

Cheers, John.

Not having looked at it very closely myself, why do you think a worn throttle spindle would be causing running problems in this carb? I wouldn't have thought it would make much difference.

Cheers John. This butterfly is bevelled both sides for a tight fit in the venturi. There are 2 tiny holes in the side of the venturi, one is covered by the closed butterfly, the other is just the other side of it, this makes up the idle device (to stop it stalling when the throttle is opened), they both go into the same jet chamber. So the butterfly needs to sit just right.

Anyway, tonight I fashioned myself a quick lathe (kind of)....



Here's a shot of the spindle I took so I would get the bits back together correctly (you can't quite see the slot, but you can see there's not much material left, although I'm sure there would be plenty for the likes of a throttle should I make one of my own)....



Anyway, the carb's back on the engine now....



& here's a shot of the decal, finally on the cowl (it's been peeled of & put back on several times)....



I won't know how well my carb work has done until Monday as I'm out all day tomorrow & it's too late to fire her up now.

Ianhw77k wrote:Not having looked at it very closely myself, why do you think a worn throttle spindle would be causing running problems in this carb? I wouldn't have thought it would make much difference.

Because that's what they do, cause lumpy running. It could be why it suffers so much when the throttle is opened, as it's admitting air through & weakening the mixture.

Anyway, it was very badly worn. We'll see if I've made any difference. I couldn't eliminate much of the play, as it seems the bushes are worn too. (but not as badly as the shaft).