# Homelite UT20046 trimmer won't start



## Bosco55David (Mar 6, 2011)

A few months ago, you guys helped me diagnose and fix a problem with a Briggs & Stratton lawn mower. Now I'm hoping you can help me again with this trimmer. 

I've owned this trimmer for a few years now, and up until last year it didn't give me any trouble. At the end of last fall I went to run it one last time and I could get it to start, but only on half choke. It would not rev much at all, and placing the throttle selector to "RUN" would cause it to die. In the last couple days I've taken to trying to repair it, and here is where I'm at. 

- Using fresh fuel/oil mix did not help. Neither did spraying carb cleaner in the carb. Spark plug looks ok and a spark tester verifies that it is receiving spark. I sprayed some starting fluid in the carb and that had no effect. I pulled the plug and sprayed some directly into the combustion chamber and that had no effect either. 

- Compression tests showed between 95-115psi. I haven't found the specs for my particular model, but from reading other posts in this forum it appears as though the compression is acceptable for a 2 cycle trimmer.

Anyways, I'm sort of at a loss for where I should go now and hope you guys can point me in the right direction. Thanks in advance!


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## duffer72 (Jul 23, 2011)

Not familiar with the specific model but all the homelites and other brands like it are notoriuos for the screws/bolts holding the cly onto the crankcase coming loose, which would give you the same type problems you are having try removing the plactis cover over the cly and see if it will wobble at all if so tighten them up and give it a try.


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## Bosco55David (Mar 6, 2011)

duffer72 said:


> Not familiar with the specific model but all the homelites and other brands like it are notoriuos for the screws/bolts holding the cly onto the crankcase coming loose, which would give you the same type problems you are having try removing the plactis cover over the cly and see if it will wobble at all if so tighten them up and give it a try.


Wouldn't that result in a loss of compression though?


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## shazif (Oct 8, 2011)

duffer72 said:


> Not familiar with the specific model but all the homelites and other brands like iphone repairs it are notoriuos for the screws/bolts holding the cly onto the crankcase coming loose, which would give you the same type problems you are having try removing the plactis cover over the cly and see if it will wobble at all if so tighten them up and give it a try.


me also think that it may cause to reduce the compression .... what you think ?


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## duffer72 (Jul 23, 2011)

Not nessecarily, if you think about it the cly attaches to the bottom half of the engine(crankcase), the compression accures between the piston top and the clyinder and cly bore area both of which are above and seperated from the crankcase other than the intake port, being loose this allows an air leak to occure the same as a loose carb or a bad crank shaft seal. I'm just suggesting the idea from my many years of experience in the business and many years of repairing the throw away brands.


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## geogrubb (Jul 28, 2006)

I agree with duffer, if you can get it to run at all try spraying carb/brake parts cleaner behind the carb and along the crankcase mating surfaces, if the engine tempo changes you have found a leak and can take the appropriate action. Have a good one. Geo


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## Bosco55David (Mar 6, 2011)

duffer72 said:


> Not nessecarily, if you think about it the cly attaches to the bottom half of the engine(crankcase), the compression accures between the piston top and the clyinder and cly bore area both of which are above and seperated from the crankcase other than the intake port, being loose this allows an air leak to occure the same as a loose carb or a bad crank shaft seal. I'm just suggesting the idea from my many years of experience in the business and many years of repairing the throw away brands.


Ok, I see what you are saying now, I'll check the bolts and see if that is the problem.


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## John Lolli (Nov 3, 2005)

I now use the suggestion from this board of red loctite on these bolts when one comes in. I have also read where others use red loctite plus lock washers. I have found these bolts to be loose on Craftsman blowers in particular.


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## duffer72 (Jul 23, 2011)

Thats what happens when they make cheap, 2 screws holding cly on, one crank shaft support bearing, one piston ring, no clutch etc etc etc, if they built cars like that they would be called go karts.


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## Bosco55David (Mar 6, 2011)

Ok, I got a chance to pull the trimmer apart yesterday and nothing appears loose or wobbles. Bolts were all still tight. What should I check next?


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## Bosco55David (Mar 6, 2011)

Any ideas?


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## geogrubb (Jul 28, 2006)

Bosco55David said:


> Any ideas?


Have you removed the muffler and checked to see if the exhaust or spark arrestor is carboned shut, if they are it wont run or will run poorly. Have a good one. Geo


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## Bosco55David (Mar 6, 2011)

geogrubb said:


> Have you removed the muffler and checked to see if the exhaust or spark arrestor is carboned shut, if they are it wont run or will run poorly. Have a good one. Geo


They looked good on cursory inspection, but I'll take a better look in the morning.

One thing I noticed is that the primer bubble is brittle and deteriorating. Not sure if that might have something to do with my troubles though.


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