Werowance builds a webster

[Brian Peters]

sorry about the redundant answer to a problem on page 2 lol will get the hang of this soon only respond to the end of the thread Durp as my son would say

 

[Brian Peters]

got my bearings in and also helped someone out with making a new handle bolt for their gun safe and now I'm back to work on the engine.

on laying out the inside radius I just cant seem to get it right. attached is a drawing of where I'm having trouble and if I move my table up and to the right by .250 in both directions from where the lines intersect which I have circled then that is where I should drill a .500 hole to get a .250 radius correct? when testing it with layout dye and my compass set with one point in where the drill puch mark would be and the other side of my compass extended out by .250 it just wont intersect with the lines correctly. seem to be at the least to far to the right. so what can you think of that I'm doing wrong or how would I locate that drill to get the radius. I realize I could just omit the radius but part of the fun is learning (to a certain extent). so basicly if measure from the far right hand of the part to the left I was measuring 3.250 and scribed a line up and down. and then (measurement not shown in the pic) looking at the part on the far right hand that part is 1.250 high so I measured 1.500 high and scribed a line from left to right and from where my to scribed lines intersected I thought should be where the .500 drill would go. but in testing it misses the mark.

View attachment 107252

 

[Brian Rupnow]

You will need a head gasket.

 

[werowance]

actually I do have a copper head gasket. I was just talking about the valve block. although I didn't specify that. and on that subject I figured I would use copper head gasket spray like I use on the farmall non coated metal head gaskets and spray both sides of the copper gasket. (no sprays or glues on the valve blocks - only paper gasket if I have to on those like you mentioned)
then on the carb, I was thinking instead of locktight I might try the tefflon paste like you use for screw in fuel lines going in a caborator. that stuff sets up almost like glue after a few days, figured it might hold it.

anyway last night I was cleaning everything and getting it back together and discovered yet another part I didn't make. the jam nut for the bottom side of the tappet. I didn't have a single 4-40 nut in the shop so I took a piece of 1/4 brass hex rod and made one. then got everything assembled enough to drill and pin the fly wheel and locktighted the jig in place - which I should be able to break loose after the drill relatively easy.

 

[CFLBob]

werowance, what kind of finish did you use on the flywheel web? It looks like wrinkle paint.

I'm chugging along, but between fixing a dozen other things around the house and other stuff, it's real slow going right now. I have done powder coating before and was considering just using black powder coat.

 

[werowance]

yep wrinkle paint. the steel was hard and was taking to much time to get a nice polished finish on the inside areas of it so I opted for wrinkle paint. fairly high temp, fuel / oil resistant etc. and easy to apply. I picked up a can at the local Napa auto parts store. ive never powder coated anything but I know what the finish looks like and I bet that would look nice on yours. I to understand the fixing things. I have to re-fix my truck this weekend. evidently I didn't get something right when replacing the ujoint on my truck. something ive done on other trucks and equipment in the past many times but something isn't right. its a singing when driving it now was quiet when first replaced but a couple weeks and its a high pitched whine now. so that's why ill be doing when I get home tonight. driving the wifes car today man I hate that teeny tiny thing.

 

[werowance]

hiding the scratches in first picture which the camera just doesn't show just how bad they really were with the wrinkle paint in the second picture.

 

[CFLBob]

Good lucking results. I'm not sure how'd get that with powder. Some combination of masking, I guess, but I'd have to look into a brush on mask.

 

[werowance]

what I did was take wide masking tape and cover the entire flywheel, then took a razer blade and trimmed out the center section. I used 2 layers of masking tape first. that way everything but the inside was protected. don't know if that would work with powder coat though

 

[CFLBob]

The main difference is the heat soak on the powder coat. I had some light green polymer tape and pieces that came in a sampler. Might still be out in the shop somewhere.

 

[Brian Rupnow]

When I worked for Volkswagen of Canada I designed all of the vacuum guns used to vacuum the powder paint out of the wheel nut wells on the cast aluminum wheels before they went to heat cure. They were amazing looking 5 barrel pistols with vacuum thru the barrels. They looked like sci-fi death ray pistols. Werowance--I tried copper head gaskets but could never get them to seal. Finally, in frustration, I just used 0.030" water-pump gasket for a head gasket. It sealed perfectly and I've never had a problem with it.---Brian

 

[werowance]

well its very late and I have had family over for a nice dinner. I have hopefully everything ready for startup. my question is what is the normal accepted rotation for running. as observed from the valve / rocker arm side should it be clockwise or counter clockwise?

I found another mistake but ill elaborate on that once I have better internet. just to say I corrected it.

also I liberly sprayed the copper head gasket with copper head spray on both sides. normaly I would spray a farmall on both sides of the gasket, the block head deck and the head itself. and immediately put parts together. right now there seems to be a good amount of suction from through the carb.i cant see the valve move on intake so I am concerned but there is vacume and release. I expect to fight with it for a long while

oh and the carb to carb adapter is sealed up with Teflon paste. it cured up tight and snug hope it stays that way

 

[Brian Rupnow]

Well, actually, look at it this way---you set the crankshaft so the piston would be at 15 degrees before bottom dead center when you drilled the crankshaft and flywheel. The flywheel should turn whichever direction it needs to make that 15 degree angle even smaller.

 

[werowance]

i have spent most of my day trying to get it to run. assuming that 15 deg before top dead would just be moving the jig I used to drill and pin the flywheel and crank to the opposite end of the crank throw and I set the ignition timing. now heres what I get. a few pops, burnt oily fuel and when it pops it kicks a little. using a rubber wheel about 4 or 5 inch in diameter on my drill rubbing the outside of the flywheel it will pop forward and exceed my drill for on or 2 kicks.
it is certainly broke in better and spins over eaiser.

the intake valve spring was to strong. I found an old grinder with a busted head that the brush springs seems to be just right. I can see the intake valve move now an on a slow turn over I can hear a whine of the intake. kind of a whistle or a sigh noise.

on the cylinder and copper gasket I do have a leak around at least one bolt hole if I load it up with fuel it will bubble out around the edge of that bolt hole. at this point I disassembled and noticed the screw at that point of leakage had dug into that gasket a little. a little work is required here to fix that leak.

I tried coleman fuel which was about 15 years old, does that stuff go bad? it still burns my lantern....
I tried nitro fuel that I used to use on my dune buggy and got a lot more fires and kicks from it.

I have so many questions and am so anxious I cant stand it lol. so excuse my annoyance lol

1. is my ignition timing question right?
2. what was the gasket or oring Brian used from a pump for the head? I have some rubberized gasket sheet I could use if that's acceptable?
3. what do you think about the fuel? nitro or coleman and the shelf life of coleman?
4. carburetor - im using the common traxxas carb, how many turns from bottom to open is considered close enough for start? and about what amount of throttle should it be at? seems 1/4 or a little less sucks fuel better.

sorry for being so needy. once I post this im gonna go eat and then re-read several posts.

 

[Brian Rupnow]

Ignition spark should occur approximately 15 degrees before top dead center. I used a piece of 0.030" thick plain waterpump gasket for a head gasket. Don't use rubberized gasket---it will melt. As far as I know, Coleman fuel in a sealed can doesn't go bad. I wouldn't use Nitro fuel. You can google "Traxxas carb settings" and the factory settings are fine--don't change them. Throttle setting should be just slightly open for start up. Make sure to use some kind of gasket between the 3 carburetor/exhaust mounting plates, even if its just brown paper bag stock. I am not a fan of friction wheel starts. I like the kind of starting arrangement I have in my build thread much better. Good luck!!--Brian

 

[minh-thanh]

werowance !
I usually use this glue for head cylinder

 

[werowance]

getting close. i think i have all the compression leaks taken care of now. getting some good pops and a long string of them together - enough to where i think its starting but when i remove the drill it wont keep going. cylinder is getting hot and is throwing carbon oil out the rear. i switched back to coleman fuel and now that's doing better than the nitro was. the picture below is mostly from the nitro fuel mix but some of it is from the coleman fuel (the black sludge). tonight ill try 2 stroke 40 to 1 mix i have for my weedeater and see how it does. then ill fiddle more with the ignition timing to. which i have fiddled a lot with already.

 

[aka9950202]

I found my engine ran well on petrol. Raw fuel or 40 to 1 2 stroke fuel.

Looking forward to seeing a video of your engine running.

Cheers,

Andrew in Melbourne

 

[Brian Rupnow]

Time for a little analysis. You obviously have fuel in the tank. The fuel level in the tank should never be above the center of the carburetor Best scenario is that when the tank is full to the top, the top should be 1/2" below the centerline of the carburetor. Next thing will be the ignition timing. If you have an old "points" system, just lay the sparkplug somewhere on the engine and turn the engine over in the direction it is going to run. You will be able to hear and see the spark, and this will prove to you that the spark is coming at the right time in the engines running sequence, about 15 degrees before the piston reaches top dead center. If you are using electronic ignition, make damn sure your sparkplug is held securely to the block ---if it doesn't have a good solid connection to the block it will burn out your hall effect sensor. Keep on turning the engine in the direction of rotation and watch the exhaust valve--it should begin to open just before the engine reaches bottom dead center, and should fully open and remain open until just before piston reaches top dead center. You don't want it to stay open past top dead center, or your engine won't pull fuel mixture in during the intake stroke. That is your valve timing.-----Assuming your engine is timed properly, both spark and valve timing, leave the sparkplug wire off, put the sparkplug back in and give the flywheel a flip with your hand, again in the direction you have chosen for the engine to run. The engine should "bounce back" against compression. If it doesn't bounce back, then it is not holding compression. Take out the sparkplug and squirt some 30 weight motor oil down the sparkplug hole.--Flip the engine upside down and drain out any oil that will come out of the sparkplug hole. Set your engine back upright, put the sparkplug back in, and flip the flywheel again. If it now bounces back against compression, you will know that your rings are not sealing. If it still doesn't bounce back, then your valves are not sealing. If it seems that the rings are not "bedding" properly, take the sparkplug out, set your engine up on the bench, oil everything really well, and drive your engine using an electric motor for two hours. Use pulleys that give a 3:1 ratio so that your engine is turning at about 600 rpm. (most electric motors are 1800 rpm.). If your rings don't "bed" after running things like this, then they are probably never going to "bed" and seal against compression. If you determine that the valves are at fault, then disassemble things and relap the valves with 600 grit aluminum oxide lapping paste. This covers just about everything I know about how to get a new engine to run.--Good luck!!!---Brian Rupnow

 

[werowance]

i have good spark and can see it. fuel tank for the most part has been below the carb hose barb however I have tested with it above that level and actually got better results like that but with each change I put everything back to how it "should be" and start out below the level.

on ignition timing I used the same jig for 15 deg before bottom dead center and just moved it forward so the piston is 15 deg before top dead and set the points.
I do get a bounce back and it actually seems to be trying to run backwards or is kicking a lot when firing with the drill. I have tried retarding the ignition a little bit and also advancing it a little bit and neither helped.

one thing I will say. the more I spin the engine the free-er it gets and is starting to break in. I'm wondering if that's why its starting to pop a lot more on coleman fuel now.

valves are still a question for me. I put a weaker spring on intake and can visually see it open on intake and can also hear a squeak when I slowly hand turn it and it sucks in through it. if I hold the valve shut I get no squeak and hard to push over.

on the exhaust I did put a slightly weaker spring on it to but still way stiffer than intake. but the original spring was way way to stiff. the new one is definitely strong enough to prevent opening on intake suction.

and also the cylinder does get really hot when its doing that firing like its going to run but just doesn't. I really hope its not the valves........