Valve Caps

cheffy_2

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Hello All,

I am getting a little frustrated with a second hand engine I have bought.
15.5hp OHV single cylinder briggs.

Model :
285H77 0173 E1 101701ZA

It didnt want to turn over and didnt have a spark.

I have adjusted the Valve clearance and swapped out the Coil.

Engine Now turns over as it should Sparks as it should.

I have looked for the Compression release bump on the cam and can see it working. The valves move as it should and it ' feels ' like it has good compression. I have cleaned the carb out (for good measure) as it had been sitting for 12 months.
Currently the engine will just not fire up. I have tried the tea spoon of fuel in the cylinder trick.

My next step is pull the head and check the piston and valves.

Before I do I was hoping for some advice as No matter how much i search I want a definitive answer on something.

On the end of he Valve stems ( underneath the rocker arms ) there are no little caps.

In the parts diagram, I can only see 1 pictured. in the repair manual it states replace if fitted, but being a second hand engine I have no idea if they were fitted and lost, or never there to begin with.

I thought ( hoped ) I had a bent push rod, pulled them out but they are both straight, then I checked the length of them.

The Steel 1 ( exhaust ) is slightly longer than the aluminium.

Only information Ive read online is if there is 1 cap fitted it goes on the exhaust, If my exhaust push rod was smaller I would put 1 on it and the rods would end up the same length, and all would make sense, but being as its the alum 1 which is shorter. to my engineers mind it could mean the intake valve isnt opening fully ( ie the thickness of the cap ) not getting quiet enough fuel, but as I say Ive put cleam fuel direct into the spark plug hole.

I may be getting bogged down worrying over something which isnt an issue.
My real question is can any 1 tell me if this engine should have 1 / 2 caps and
If this engine was missing 1 / 2 caps would this prevent it from starting?
 

Rivets

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Thank you IL, I missed that one. Sorry Cheffy for the bad info. Guess I better get another cup of coffee before I post in the morning.
 

ILENGINE

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Thank you IL, I missed that one. Sorry Cheffy for the bad info. Guess I better get another cup of coffee before I post in the morning.
Rivets, don't feel bad about missing it. Sometimes the parts locations are not well defined on the schematics. I have had to call up my distributor a couple of times and say I am looking for this part, what diagram is it on.
 

cheffy_2

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ILENGINE

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I don't see it having a big effect on starting. Could possibly effect valve timing slightly due to the rockers hitting the retainers before the valves. Have you checked the flywheel key to see if it is offset or sheared.
 

cheffy_2

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I don't see it having a big effect on starting. Could possibly effect valve timing slightly due to the rockers hitting the retainers before the valves. Have you checked the flywheel key to see if it is offset or sheared.
Ill put that top of my to do list ( before taking the head off )

Appreciate your support in this!!
 
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