Roper 8 hp Won't Start

[reynoldston]

I wish I had a compression tester. Mine is metric and won't fit in the spark plug hole.

Anymore thoughts would be greatly appreciated.

The standard spark plug hole is metric. 14MM. I have never seen anything differant then some older cars and tractors had 18MM. When I say older like back in the 1930's.

 

[Berniebac]

The standard spark plug hole is metric. 14MM. I have never seen anything differant then some older cars and tractors had 18MM. When I say older like back in the 1930's.

Well, you would think that it would have fit. I'll try it again and see if I can get it to go in. I didn't want to force it for fear of stripping the gauge or the spark plug hole. It is in a difficult spot to get it to align with the plug hole. You have to put it in thru the grill and try to line it up.

Thanks

 

[Berniebac]

The standard spark plug hole is metric. 14MM. I have never seen anything differant then some older cars and tractors had 18MM. When I say older like back in the 1930's.

I tried again and with some gentle twisting it did go in. I used my jumper pack to roll the engine over and it shows only about 70 psi. Not sure that is enough to make it worth rebuilding this thing or not.

I won't quit just yet, we'll see where it leads to.

 

[Berniebac]

Thought I would provide an update. I picked up a carb kit and cleaned the carb out. Struggled to get the carb kit complete, but With the help of Rivets, I got it together correctly.

Put the carb on tonight, hooked up the gas line and hit the key. It started. Ran rough, with some black smoke that I hope will disappear when I get a chance to adjust the needles on the carb. Tried it in each gear and the tranny works (it's up on blocks at the moment, no wheels on it).

I think I will start to strip the body panels off and strip and paint them.

 

[Rivets]

Congratulations, now let's adjust that carb. 1. Start the engine and bring up to full throttle. 2. Slowly back out the high speed needle until the engine starts to bog down. 3. Slowly turn the high speed needle in until it starts to bog down and then out 1/4 turn. It should now be running pretty smooth. 4. Let's start on the idle circuit by bringing the throttle down as low as possible to stay running. 5. Repeat steps 2&3 on the idle needle valve only turn the idle needle 1/8 turn at the end. If you did it right it should run smoothly through all speeds. Good Luck.

 

[Berniebac]

Congratulations, now let's adjust that carb. 1. Start the engine and bring up to full throttle. 2. Slowly back out the high speed needle until the engine starts to bog down. 3. Slowly turn the high speed needle in until it starts to bog down and then out 1/4 turn. It should now be running pretty smooth. 4. Let's start on the idle circuit by bringing the throttle down as low as possible to stay running. 5. Repeat steps 2&3 on the idle needle valve only turn the idle needle 1/8 turn at the end. If you did it right it should run smoothly through all speeds. Good Luck.

I tried to adjust the carb today by following your instructions. I only got to Step 3 as I was turning the high speed needle in, the revs were increasing and it was running very smooth, but all of a sudden it just stalled. I did get it started once more after that, it ran at high revs, then stalled again. Maybe I got it a little too lean????? My booster pac is out of power so I have to recharge it before I can go further.

I said I would post a few pics once I got a chance. I am concerned about the throttle stop screw as the screw does not turn in far enough to touch the stop. I can't see how this can be used for adjustment, if it does not touch the stop. I suspect someone has tinkered with the governor so that the governor link and the link spring are not in the correct position. It is hard to see as the pic is blurry, but you can see the screw is a long ways away from the stop. I took this pic looking in from the side through the hole the muffler is supposed to come thru. The other two pics are shot from the top looking down on the carb and the governor control plate. I hope these help show what I am working with.

You will also see that someone sprayed paint on some of the cooling fins for the engine. I am going to have to get that off of there somehow, if I get this to run.

 

[Berniebac]

I took a video of it starting and running and provided the link below. I am not the best videographer, so my apologies for the shaky camera that drifts off the subject.

102_0001.mp4 video by Berniebac - Photobucket

I made the adjustments to the carb as suggested by Rivets and have it running as smooth as I can get it. I still have two problems that I would like to clear up if any one can tell me what they might be and what the fix is.

First, the engine makes a popping noise that seems to go along with the sputter coming out of the exhaust, but when you are standing at the engine you can hear this pop, pop ,pop.

Second, the exhaust fumes really stink. I don't see a lot of smoke from the exhaust, but the fumes are awful.

Any help greatly appreciated.

 

[Rivets]

Sorry I haven't been back to you and I don't have time tonight, but I hope to have time tomorrow to offer some advice.

 

[Berniebac]

No problem. I am not in a panic to get it done. Its a project that will take me a while to complete. I appreciate any help you can offer.

 

[Rivets]

Forget to tell you don't run the engine for more than a couple minutes without shrouds. They are a big part of the cooling system, and you can overheat the engines very fast.