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Discussion Starter #1
I have a 2004 Tecumseh LH358SA and need to adjust both valve clearances. The current intake clearance is .005 and the exhaust is .007. This is first time I am venturing into any kind of valve work on a tecumseh L-Head engine. Been tinkering with them for 20 years but never with valves. Recently purchased a valve spring compression tool and raring to get started.

I have read many of the threads in the forum on this subject. I am so confused on what the correct clearance is for each of the valves that my mind is spinning..

I have 2 Tecumseh service documents from internet that conflict each other. One says the intake clearance is .008 and the exhaust clearance is .012. Another document say both have min max range of .008/.012.

I don’t want to screw this up.

Can somebody please let me know what I should set the clearance at for each valve.

Also I do not have access to a grinder so was going to use a file on the valve ends. As I file do I have to reinstall the spring to check the clearance or can I just hold the valve down with my hand to take a measurement until I get it right.

The forum has helped me so many times I am hoping my questions will get answered by weekend..

Thanks.
 

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I use the 3-11 L-Head manual on this page for references when I work. I think I have seen that discrepancy that you mentioned, but I believe that it is a min/max tolerance of 0.008 / 0.012". Also, my local shop guys said min/max right away on my 1995 7 hp engine. I check the clearance without the spring when grinding the valve, but first make sure the valve and seat are clean (I usually lap the valves to ensure clean tight fit). Finally, if you have a good micrometer you can file then measure, repeat till you have removed your estimated amount. But make sure you file/grind perpendicular to the shaft.

Tecumseh Service Manuals

Hope this helps.
 

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I've heard people mention staying towards the large end of the clearance range (like 0.012", not 0.008"). The clearances tend to get smaller over time, so it gives you more time within the range, before they're out-of-spec again.
 

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Just did it for the first time not too long ago and came across the same descrepincy from .008/.012 but that is the high and low, I was doing it on a old beater machine just to do it so was’nt worried so much if I messed up, I did however grind too much on the exhaust and can get the .015 in but it still ran a lot better than before I started lol and it didn’t cause any issues with the decompression for starting so if you go slightly more it should be ok.
 

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When I did mine, I didn't undo the springs. I used a tool ( don't remember what type) to push down on the springs and insert an ignition file.
Funny thing is with the valve clearance where it should be I now have lost the decompression for easy pull starts.
So I use the electric start.
The engine does have more power though.
 

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Discussion Starter #8
Update. It’s Saturday night I have no life so I thought I would tackle my valve work on this TEC.

It took me a while to figure out how to use the new valve spring compression tool.

I worked on the exhaust valve first. Checked clearance before removing valve and it was a snug .007. I set the valve between 2 pieces of wood in my vice and filed 8-10 strokes at a time on my my hands and knees to make sure file was as perpendicular as possible. After checking the clearance on the 4th time it was at .011 and that is where I left it for fear of removing to much from the valve. The valve itself and the seat looked very clean to me no pitting at all so I did not lap it.

I worked on the intake valve next. The spring was very difficult to compress as the top cup over the spring was flat and not curved as the exhaust valve. Very hard to get the jaws of the compression tool between the housing and that flat washer like fitting over the spriing. Question.........Is this normal? I would have expected both top fittings on each of the springs to be the same?

The clearance on intake valve was .005 before I removed the spring. Using same technique in vice as exhaust valve I filed till I got to .011 and then installed the spring. Still not sure if this flat washer like fitting on top of intake spring is normal.
The seat and valve looked as clean and smooth as the exhaust so I did not lap it either.

I ran out of energy so this is where I stopped. Tomorrow I will put the head back on and torque it and put the rest of the parts back and try to start it up.

Stay tuned and a big thanks to all that have replied.

The forum ROCKS.
 

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I also find some difficulty in removing the valves with the common valve tool, especially getting the tool over the top of the upper valve spring cap. Installation is much easier. You should look up the part numbers, but on my Tecumseh engines so far the 2 spring caps were the same part numbers.
 

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Discussion Starter #10
I just checked the parts diagram and they are definitely different part numbers and look exactly like what I removed. Intake is called a valve seal cap and exhaust is called a valve cap. Now I am not sure if I installed the intake valve seal cap correctly. Looks like it has an o ring that fits in hole where valve stem comes down. I hate the thought of removing that **** intake spring again. It was a nightmare.
 
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