18 replies to this topic

[GTTinkerer]

I am working on a Bolens 1053 with the Wisconsin TRA-10D engine that I rebuilt the carb on that won't start. It has been sitting for about three years. Fresh gas. Engine fires when trying to start but just not enough to keep it running. Compression is about 65 psi. Spark is there but pretty weak when check with the inline tester. Spark intensity doesn't change when grounding out the points side of the coil with a jumper wire which should mean that the points and condenser ore OK.

Only things I can think of are either low compression or weak coil. Going to try putting a little oil in the cylinder through the spark plug hole and see if compression comes up. Looking for suggestions.

Thanks,

[Bolens 1000]

These engines were furnished with a compression release so there's really no way to get an accurate reading. I would say you have good compression if you are getting 65.

Are you sure the engine is timed properly?

[GTTinkerer]

Added about an ounce of oil, compression jumped up to about 95 psi. Put in the spark plug and the engine started and ran for about two minutes and died. No restart and compression is at 70 psi. Time for a rebuild I think.

Edited by GTTinkerer, September 16, 2012 - 09:12 AM.

[GTTinkerer]

These engines were furnished with a compression release so there's really no way to get an accurate reading. I would say you have good compression if you are getting 65.

Are you sure the engine is timed properly?

I haven't checked the timing. The tractor has the hydraulic pump and it will have to be pulled off before I can get to the points cover. Pump is froze up so it will need to be pulled to be fixed anyway. I'll check the timing before I pull the head to mic the cylinder just in case.

I sure am glad he decided to have me fix it instead of selling it to me though.

Edited by GTTinkerer, September 16, 2012 - 09:18 AM.

[8tyman8]

i would check with a in line spark tester as that when compression builds it requires more voltage to jump the gap it might be a simple points sanding or a new spark lead

[GTTinkerer]

i would check with a in line spark tester as that when compression builds it requires more voltage to jump the gap it might be a simple points sanding or a new spark lead

Thanks for the suggestions. I have been using an inline tester and used it to by-pass the plug wire so pretty sure it isn't the problem. As far as the points I by-passed them by jumping the points side of the coil with no improvement in spark quality.

Checked the timing by the book and can't get it to fire on the timing mark. Best it will do is about 5* (half and inch) before it should fire. Pulled the points and they are burnt pretty badly, only thing I can figure on the timing is the stationary side if the points may be burnt down to the point that they can't be adjusted to specs.. Also the jumper strip is coming apart. I'll order a new set of points, condenser and jumper strip. Going to find Daniel's coil post and order a new 12 volt coil for it if the points and adjustment doesn't help.

Thanks for the suggestions and send more if you have them.

[JDBrian]

Weak spark is probably the problem. When you get to a nice snappy spark and it still won't run you've got to look elsewhere. There are usually a bunch of marginal things in these old engines and then suddenly they just won't run. Fix one thing and the next one rears it's head. Good luck getting it sorted out.

[KC9KAS]

As stated above, clean & file/adjust the points and maybe a new coil for a better spark.

[GTTinkerer]

I ordered a set of points and a condenser from NAPA but don't know for sure when they will be here. Rolled it off the table and rolled on a customers MTD tiller while I wait.

[GTTinkerer]

Got the new points set and condenser installed. Used the inline spark tester to time the engine by slowly rolling it over by hand and watching for the tester to flash and used the points to adjust it so it is right on the mark. Checked the point gap and it is a snug .020". Spark was still a little weak with the tester and orange with a new AC spark plug. Replaced the coil with a new 12 volt one from NAPA. Spark much better with the tester and blue with the spark plug.

Tried starting the engine and it is still only hitting once in awhile but not enough to keep it running even with a shot of starting fluid. Checked the compression again and it is at about 70 PSI. About ready to take it to a pond and see if it will float. But instead ordered a new Champion D21 spark plug which won't be here until tomorrow morning.

I think I'll go out and make sure the flywheel key is not sheared since it seems like the engine maybe firing a little early and kicking back every once in awhile. But the the point gap when wide open is right though.

Did Tecumseh built the Wisconsin engines?

[GTTinkerer]

Since I am running a 12 volt coil I am not using a ballast resistor. As far as the plunger it is opening the points where they should open and when cranking it over the timing marks are aligned with a timing light. Supposedly it ran a couple years ago but the carb was leaking. I rebuilt the carb no more leaks. It is getting fuel to the spark plug and will fire some when turned over but not quick enough to keep running

Edited by GTTinkerer, September 19, 2012 - 03:09 PM.

[Bruce Dorsi]

Check the primary voltage at the coil while the engine is cranking. ......If the battery is weak, or if the starter is placing too much load on the battery, the primary voltage will drop, creating a weaker than normal spark.

If you are getting a strong spark while cranking, but it's not running, I would then pull the head to check for valves seating and valve timing.

I have seen a few Wisconsins with a broken camshaft that do some crazy things.

I know you have a lot of experience with small engines, so I know you are not overlooking anything obvious!

[GTTinkerer]

I gave it the day off to rest and will put in a new plug and try it once in the morning. If that doesn't work I'll pull the carb to get to the valve cover and check the clearances. Still with 65 to 70 psi it doesn't seem that compression would be the problem.

Talked with the owner today and he said he had the same problem when he tried to start it a couple of years ago. Would have been nice to know a couple of weeks ago.

[GTTinkerer]

Finally got back to the Bolens after over a week of putting out honey-do fires. Pulled the head yesterday and lapped in the valves after digging out the carbon left by the need for an overhaul. Turned over without sounding like there was no compression release but still only putted until the key was released and then she died.

This morning I removed the starter belt and wrapped a rope around the pulley and gave her a yank and it fired up and after adjusting the carb ran fine. Looked at the starter/generator and saw that the pulley was only about 2" in diameter so I pulled a three inch pulley off another starter/generator, swapped them out and presto she fired up. Called the owner and it turns out he switched starter/generators when the initial problems started awhile back. My only issue is why the engine and starter/generator are all the same color though but perhaps he only changed the pulley..

I guess I can go to bed now since I already learned my something new for today.

Thanks again for all the earlier replies.

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Edited by GTTinkerer, October 02, 2012 - 12:38 PM.