acdii

Well, the only other Bruce I know is no longer a Bruce IYKWIM

Glowgeek

Whatchu talk'n bout Willis?

acdii

Eh Hem

Glowgeek

In Ireland they call those Brucy Boys. Not kidding

Wouldn't it be easier to just share with us your first name? Can't be any worse than Loonie Lonnie.

acdii

And none of them would know what to do with a Saito if you handed them one.

jester_s1

Ok, a Saito .80 is giving me grief. I got it in a lot of stuff from a hobbyist that I trust. It was gummy, so I disassembled it and cleaned everything up. I am fairly certain I got the timing right. I set the valves to minimum lash, and I don't think they are too tight because I have good compression.
Fuel is Omega 10%
New OS F glow plug.

I reset the needles to factory setting, and can peak the HS. I got 8400 RPM at peak,. That's lower than I expected, as my prop is in the middle of the recommended range.
The big problem is idle. At roughly 1/4 throttle, I get a 2300 rpm idle at a very rich setting. It dies if I lean it any more. If I leave the glow driver on the same throttle position will be about 4000 rpm and erratic. I can lean it more with the glow driver on and go to a lower setting, but it's erratic and dies after a few seconds.

Any thoughts?

acdii

air leak. Maybe the o ring is damaged in the intake manifold.

Glowgeek

You didn't say if it looked well used or like new. Your symptoms could be caused by a number of things.

1. Engine is not broken in yet
2. Prop to large
3. Bad glow plug
4. Intake tract leak
5. Slit in spray bar not facing toward intake manifold
6. Water in fuel
7. Bad bearings
8. Wrist pin sticking
9. Lifters sticking in bores
10. Valve sticking
11. Valve leaking
12. Broken valve spring

As far as it being out of time I'm not sure, I haven't heard one run that way.

jester_s1

Thanks for the help.
I'll go back through the carb then. I put new bearings in, the engine has some wear so it's definitely broken in, new glow plug, no spraybar slit, fuel ran fine in my Novarossi last week, wrist pin and lifters are moving freely after the cleanup last week, valves don't feel sticky when moving manually and seem to be sealing well (good compression), valve springs are good. So I guess an air leak somewhere is what I have left.
I didn't say this before, but it sounds to me like the engine goes lean at less than 1/4 throttle. It just quits suddenly.
Is there a way to check the timing without taking the timing gear off again?

Rudolph Hart

A long time back i miss timed one and had a similar experience. Take the plug out and find tdc on the exhaust stroke. With the rocker covers removed you should see that the pushrods are of an even height. Now if you wiggle the prop back and forth the pushrod tips should move up and down the same amount. Good luck.

ps bruce you've ruined a lot of movie memories for me

Glowgeek

Jester, next time you have your cam box off you can make a tool to set the timing. It's just a stick of metal rod the same OD as a lifter with a point ground on one end. There is a hole in the cam on the base circle of the intake lobe that is used for cam timing alignment by inserting the tool into the intake lifter bore and into the cam hole. The tool holds the cam in a fixed position while installing the cam box onto the case with the crank pin at TDC.

modeltronics

My Feedback: (27)

If you search the web you can find a tool that I was going to machine. Then Hobbsy (Dave) showed me a simple tool that can be made in 30 second with a scrap piece of Nyrod. I hope he still has a picture of it because that is all you need. I like it because it is so simple.The Nyrod has a small piece of 2-56 threaded rod screwed in it that fits the hole in the cam. The Nyrod fits perfect in the pushrod hole in the cam cover. It works perfect and is simple and easy to make.

Pete

Glowgeek

Hey great, thanks for sharing. Yeah, Dave has some good tricks up his sleeves.

Hobbsy

My Feedback: (102)

A Sullivan Golden rod 1" and a piece of 2-56 all thread cut to .125, eazy peazy.

Super easy. It's precise too.

jester_s1

Well you guys can take the complication out of anything!
I did see the tool suggestion when I read a thread on tear down and reassembly. I had thought about making one from the right sized nail, but I figured it couldn't be that hard to line it up right long enough to put a bolt in it. I'll make a nyrod tool and check the timing when I put new o rings on the carburetor.
If I understand it right, I should be able to put the tool in so it engages the cam hole at the same time the piston is at TDC, right? So I could use it to check the timing without taking off the gear housing?

Jesse Open

Glowgeek

Jester, you have to get the intake lifter out of the cam box to put the tool in. That requires, at the very least, removing the 2 carb screws, lifting the cylinder and removing the intake push rod, push rod tube and the lower push rod tube seal. You may then be able to get the lifter out with a strong magnet.

I find it easier to remove the back plate, cylinder and cam box as well. Just makes it less frustrating for me to get the lifter out. I leave the carb and intake attached to cylinder; less chance of damaging an oring that way.

jester_s1

Ah, I forgot about needing to get lifter out. I'll reset the timing and do the orings. I'll let you guys know how it turns out.

the Wasp

My Feedback: (1)

jester_s1, thank you for calling it Nyrod, I bought 2 packages of it 18 years ago and I only have 6 inches of it left, it's the only thing I use for the throttle linkage. but I tried to order some and could not find it. I was going nuts, no one had it, I had to have it, then I found it, it is now called Gold-n Rod, and Do-Bro makes it.

I don't like the new name, but it still works great for the throttle

Jim

Rudolph Hart

Oh things could always get worse...

Hobbsy

My Feedback: (102)

There is an easier method of checking the timing, pull the glow plug, turn the engine to the top of the exhaust stroke and the beginning of the intake stroke. At top dead center both valves should be open a little and by the same amount and when moving the crank back forth the valves should alternately open and close simultaneously.

Hobbsy

My Feedback: (102)

Sullivan Golden Rod: https://www.towerhobbies.com/cgi-bin...?I=LXFU91&P=ML

FlyerInOKC

My Feedback: (6)

I prefer these less temperature sensitive then Golden Rods.

https://www.dubro.com/collections/pu...s/36-lazer-rod

Glowgeek

Heck yeah, I'd hate for my cam timing to go out of trim!

Seriously though, I haven't tried those dubros.

erieqc