Yet Another Webster Begins

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on mine, i ended up not needing a head gasket at all, but an old tide soap box would work as well. but min ran fine with no gasket at all. my only problem was ignition timing vs valve time was done exactly oposite of what it should have been done. once i corrected that it started right up.

now on starting. will you be putting a drill start lug on your crank? i didnt what i used was a rubber disk i got at the auto parts / paint store. its used for removing the glue or double stick tape on body trim and vent visors and such. chucked it in my drill and just pushed it against the fly wheel and i turns it over pretty easily
 
I actually don't have a head gasket on mine either. I did add some paper gaskets for the valve body parts as I could see a few bubbles in a couple of spots, but that was after my initial runs. If you feel compression and the intake and exhaust seem to be working correctly, it will probably run without gaskets. You should be able to tell if you have leaks and where they are. Ultimately though, you may end up adding gaskets. No big deal.
 
now on starting. will you be putting a drill start lug on your crank? i didnt what i used was a rubber disk i got at the auto parts / paint store. its used for removing the glue or double stick tape on body trim and vent visors and such. chucked it in my drill and just pushed it against the fly wheel and i turns it over pretty easily

I was just looking at some pictures of those yesterday. Hadn't really thought it out, but I should.

I don't think I've ever heard of or seen the thing you're talking about for removing the glue or tape residue. Do you have a picture in your build thread? Or some kind of product name I can search on?

I actually don't have a head gasket on mine either. I did add some paper gaskets for the valve body parts as I could see a few bubbles in a couple of spots, but that was after my initial runs. If you feel compression and the intake and exhaust seem to be working correctly, it will probably run without gaskets. You should be able to tell if you have leaks and where they are. Ultimately though, you may end up adding gaskets. No big deal.

Thanks, Scotty. I used rectangles of brown paper, like Brian Rupnow suggested. I haven't soaked them with oil, yet; I'm waiting to get closer to starting it up. I'll probably get some gasket stock at AutoZone while I'm up there.
 
For head gaskets I use 0.030" thick waterpump gasket from a local auto supply company. It is grey in color and comes in either rolls or sheets. Cardboard from a cereal box will work, I just don't know how long it will last because of the heat.
 
on mine, i ended up not needing a head gasket at all, but an old tide soap box would work as well. but min ran fine with no gasket at all. my only problem was ignition timing vs valve time was done exactly oposite of what it should have been done. once i corrected that it started right up.

now on starting. will you be putting a drill start lug on your crank? i didnt what i used was a rubber disk i got at the auto parts / paint store. its used for removing the glue or double stick tape on body trim and vent visors and such. chucked it in my drill and just pushed it against the fly wheel and i turns it over pretty easily

Hi Guys,

I've seen old printer paper drive wheels used on a mandrel for that task. I'm thinking of the plastic rubber covered type like those used in HP desk top printers.
 
here is what I am using. the link to ebay is very expensive. think I paid about 15.00 for mine, I bought it to remove the double stick tape from when I was removing vent visors from my wifes car a long time ago. - a starting lug would probably be better but I didn't do one and the disk works fine for me

on fuel I ran straight coleman camp stove / lantern fuel from wal mart. runs just fine on that.

ebay link to the ruber disks. don't buy this one because 191.21 is way to much, maybe because it comes with the air tool as well. I bought mine at napa auto parts and just chucked it in the drill

https://www.ebay.com/itm/Auto-Body-...lding-Tape-Cleaner-Removal-Tool-/272854462544
1603812281137.png
 
Thanks for the info on the pinstripe remover. I've found them online at Walmart and Amazon. I didn't check my AutoZone.

And this little post got interrupted by about 90 minutes because I have a washing machine filling the kitchen sink. Time to play plumber.
 
Thankfully, the plumbing issue was resolved with a plumber's snake.

I've been back to the Webster, resolving little issues one at a time. Today, I put up a video to show a problem I've been staring at for a few days.

I can turn the flywheel by hand and move the piston but during the compression part of the stroke the flywheel will slip and the crankshaft throw stop moving unless I drive the crankshaft throw by hand. There is no spark plug in the cylinder, just a giant hole to the outside world so there's no real compression going on.

When the piston is coming out of the cylinder, it moves much more freely.

My inclination is that it's not the cylinder because I think if that was too tight in that area, it would be just as hard pulling the piston out as pushing it in.

The crank shaft throw isn't perfectly perpendicular to the shaft and has a little wobble. I can watch the pin driving the connecting rod move in and out of the bearing a little during the rotation about 1/16" back and forth. It seems pretty easy (I have oil in there) so I don't think it's that resistance.

Comments appreciated.
 
As long as there isn't anything actually going 'kerthunk!!' when you turn it by hand, put a v-belt from an electric motor to the flywheel, coat everything with lots of oil, and let it run for an hour. That cures an amazing number of ills.
 
Don't know how hard it would be to get the connecting rod separated from the crank throw, but then you could move the piston by hand, and maybe eliminate that as a reason for binding. I don't think the crank pin being in a visibly different position in the big end bearing at different parts of the rotation is a good sign...
and likely your problem. You've had other issues with that crank throw, and maybe it's all come together to bite you.
Doug
 
As long as there isn't anything actually going 'kerthunk!!' when you turn it by hand, put a v-belt from an electric motor to the flywheel, coat everything with lots of oil, and let it run for an hour. That cures an amazing number of ills.

No kerthunk sounds. I moved the throw maybe .010 away from the side and now I can spin it with my electric drill. It has been running 45 minutes.
 
Don't know how hard it would be to get the connecting rod separated from the crank throw, but then you could move the piston by hand, and maybe eliminate that as a reason for binding. I don't think the crank pin being in a visibly different position in the big end bearing at different parts of the rotation is a good sign...
and likely your problem. You've had other issues with that crank throw, and maybe it's all come together to bite you.
Doug

I keep telling myself I could have made a half dozen in the time I've spent deciding if I need to make one. It's running comfortably now, and when I swapped batteries after about 20 minutes, I tried by hand and it was definitely easier.
 
I have found that sometimes you need a bit more wriggle room here and there to stop binding. it the con rod has a bit of room to move from side to side in the piston it will allow for some wobble in the crank disk. a vertical upshur that i made would lose compression at the top of the stroke because the crank was pushing the piston sideways, compressing the oring on one side and creating a gap on the other, half a millimetre off each side of the con rod and it was fine, after a week of frustration trying to find the problem.
 
I might get some argument on this ---but--When I build an engine, (and I've built about 40 now) I hold everything to the tightest tolerances I can manage on a manual mill and lathe, both with DRO's. Consequently, these engines are generally quite "stiff" when they are finished. Some of the stiffness can be attributed to tight tolerances, some can be attributed to a "stack up" of tolerances. If I can turn them through a full 360 degrees without any definite interferences, then I oil everything up very well and run them for 1/2 to 1 hour with an electric motor and a v-belt drive. If they don't loosen up in that time, then I've made something wrong. Probably 95% of the time they loosen up quite considerably after "running them in" and are then ready to run on their own.---Not everyone agrees with this approach, but this is what works for me.---Brian
 
I might get some argument on this ---but--When I build an engine, (and I've built about 40 now) I hold everything to the tightest tolerances I can manage on a manual mill and lathe, both with DRO's. Consequently, these engines are generally quite "stiff" when they are finished. Some of the stiffness can be attributed to tight tolerances, some can be attributed to a "stack up" of tolerances. If I can turn them through a full 360 degrees without any definite interferences, then I oil everything up very well and run them for 1/2 to 1 hour with an electric motor and a v-belt drive. If they don't loosen up in that time, then I've made something wrong. Probably 95% of the time they loosen up quite considerably after "running them in" and are then ready to run on their own.---Not everyone agrees with this approach, but this is what works for me.---Brian

Brian, you're one of the people I follow the closest on the HMEM. I've seen you talk about running in an engine like that, and seen you do it in videos. That was my goal all along.

Like I said, I was able to get it to move a bit smoother every time I played with it and now it has run for at least a half hour. A couple of days ago, if I turned the flywheel by hand, the crankshaft throw would stop moving, now it completes every revolution. The drill ran for an hour, but a few times the chuck loosened and the engine stopped moving. It was while I was looking after something else (of course) so the drill ran five minutes or more without moving the engine. I'm getting close to trying to start it and all the troubles that will fall out of that.
 
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