Intek won't turn over ( Starter??)

Hello.

I have an 18.5 Briggs and Stratton Intek motor that gets stuck on compression when the starter turns.

I have ruled out valve clearances or cam issues (took it out for inspection).
My next step is to put it back in and clean up all the cable connections.

If I still can't get the motor to turn over through at least one cycle, is there a way to evaluate the starter?

I am attempting to start the motor with a truck battery and jump packs. The mower battery is bad.

Guess I will pull the starter and at least clean it up before trying again.

You have a good 12V battery with jumper cables and this does not turn ? Just make sure connection are good.

Are you able to turn the motor by hand ? If you position it just after compression, starter stops on next compression cycle ?

backporch said:

Hello.

I have an 18.5 Briggs and Stratton Intek motor that gets stuck on compression when the starter turns.

I have ruled out valve clearances or cam issues (took it out for inspection).
My next step is to put it back in and clean up all the cable connections.

If I still can't get the motor to turn over through at least one cycle, is there a way to evaluate the starter?

I am attempting to start the motor with a truck battery and jump packs. The mower battery is bad.

Click to expand...

No offense intended but I have seen numerous incidents where people think they adjusted valves correctly but were using the wrong method. Sounds like valve adjustment OR compression release to me. Yes, I see you say you have eliminated both. IF a starter is held engaged for too long an interval, the armature wind will over heat, loose resistance and thus torque. You can tell by the looks of the winding and smell. Reddish wire will look black and smell burnt. Do not hold starter engaged for longer than 5 seconds followed by at least 10 second rest period.

I had a similar problem come up all at once. Turned out the positive battery cable terminal was nearly broken off and not carrying enough amperage.

I can send you a Service Manual If you don't have one and would like it. Address below, put in proper format and remind me engine model number and what you want.

Walt Conner
wconner5 at frontier dot com

Sounds like your auto decompression lever came off your cam or valves need adjusting.

I took the engine pan off and the cam has the decompression lever in good shape. Its all back together now.

I was pretty careful setting the valve clearances. It is actually really easy compared to what I remember with my old VW air cooled engines. .003 on intake and .005 on exhaust. I set them at just beyond TDC on the compression stroke.

I can turn the engine by hand.

I also took the starter out and apart. Everything looked pretty reasonable. The pinion gear on top was messy because there was a mouse nest on top of the motor. I have that cleaned up and moving freely. The internals of the starter look good, no broken magnets, the brushes are in good shape and no signs of burning. Copper on commutator is nice and clean and shiny.

Going to fill the motor with oil and give it another try tomorrow.

I contacted the previous owner. He didn't realize that the fuse was blown so he started the motor by jumping the post on the starter from a car battery and jumper cables. If I can't get the starter to get past TDC I am going to give that a try.

Same situation with cleaned up starter.

Motor turns until it hits compression and stops. Tried jumpering at the battery terminals and also went right to the starter lug.

Looks like the intake stops moving about 45 degrees before TDC. I can manually turn the motor. If I manually turn it to TDC it also can't get through the power stroke.. may be pulling a vacuum there.

backporch said:

Same situation with cleaned up starter.

Motor turns until it hits compression and stops. Tried jumpering at the battery terminals and also went right to the starter lug.

Looks like the intake stops moving about 45 degrees before TDC. I can manually turn the motor. If I manually turn it to TDC it also can't get through the power stroke.. may be pulling a vacuum there.

Click to expand...

When you took it apart, are you sure you got the timing marks lined up?

When i put it all back together, I kind of regret not taking a picture of it assembled. I believe I got it right...the marks were pretty clear on both gears.

I was at Lowes today and I turned one of the display tractor motors by hand. The resistance of that motor to turning felt very similar if not harder than mine.

I ordered a starter last night from Amazon. Hopefully I won't get a bum part and the new part will fix my current problem.

Timing marks should match up, on the crankshaft you have a paint mark or dimple on the gear, and on the cam the same way.


the mark on the crankgear goes into the notch with the dimple on the cam gear.