2003 Rancher ES valve issue

[shadetree 5,880]

11 minutes ago, Airbusboy said:

I MAY have stumbled onto the problem. I just pulled it down AGAIN to recheck the valves. The intake was reading about .007 and the exhaust a bit more...BUT...I did a compression check again and this time she read right at 200PSI!  WHAT?  I've got a buddy on his way over with HIS tester and we're going to see what his gauge reads. Is it possible that my exhaust muffler is clogged and that is why she's reading that high? If she can't breath at high RPM wouldn't that cause my issue that I'm getting? I just checked and neither Amazon nor Ebay has a seller with OEM mufflers so.....can you pull these apart and clean 'em out? 

no you can not pull the mufflers apart.

[Airbusboy 14]

Okay, so HOW would I acquire a new muffler?

[shadetree 5,880]

Just now, Airbusboy said:

Okay, so HOW would I acquire a new muffler?

new or used, ebay or power sports nation for used. you '' can '' take them apart ?, but it will require cutting the end open, trust me..it wont be easy !.

[Fishfiles 20,145]

Not sure your specific model , but for instance a  2003 TRX350FM is still available , Partzilla has them reasonability priced too !!! LOL , 

2

MUFFLER 18310-HN5-670  Ships in 2 to 3 days

$1,112.64 $1,034.76

 

 

You could get a after market  slip on , check with Caltic for a after market , find a used one like Shade mentioned 

[Fishfiles 20,145]

22 minutes ago, Airbusboy said:

 I DID try that 'Silent Rider' secondary muffler recently though. That thing has a pipe that goes inside the OEM muffler and turns 90 degrees to vent. I took it off already trouble shooting this problem. Reckon pushing that pipe down into the outlet of the OEM muffler could've caused this?

You never know , I doubt it could have did damage that would block the flow ,  but never lived it  --- are you getting exhaust out the muffler ---

 

I have had a exhaust valve get bent and stick one time , was hard figuring that out , that was caused by a timing chain issue , jumped a tooth and the piston hit the valve and didn't snap it , just bent it and it stuck , it would run but bad , the valve was staying opened just a tiny bit all the time -------   had anther time where it broke the valve and caused a lot of damage 

[spock 42]

Something doesn't add up here....isn't this a 350? It has a decompressor in the camshaft, right? The spec is 97 psi for those engines - and you're seeing twice that?

I'm not sure that an exhaust problem could do that, it seems unlikely. I'd be curious to know what the compression is with the muffler removed.

[Goober 1,555]

no need to get super frustrated—it likely something simple. I personally would start over.

In order of priority, I would first suspect improper valve setting.

Your compression measurement can be greatly affected by incorrect method.

 

fouled plug 

 

Did you change the enrichment valve on the carb? I don’t think it comes with carb—but quad will choke out if seal is worn.

 

improper carb synchronization 

inspect fuel tank by draining down completely—shine superbright flashlight in there to inspect outlet screen.

[Fishfiles 20,145]

1 hour ago, spock said:

 The spec is 97 psi for those engines - and you're seeing twice that?

 

 throws me off also , I was thinking the exhaust valve is stuck or not open at the correct time 

[Airbusboy 14]

FOUND it.  Big problem. The upper rocker assembly was not getting oil. That allowed the rockers, and especially the exhaust rocker to wear badly. To the point of hanging up and not closing each time. I'd get the valves adjusted right, pull it through with the pull starter a few times, and then the exhaust rocker would be locked. You could TAP it and it would let go. On top of that, the top of the push rod on the exhaust side was flattened. A new rocker shaft, rockers and push rods would be required but only AFTER I figure out WHY no oil was getting to the top end. The passage in the valve cover was clear, but no oil was coming up around the shaft that feeds that boss. So now the question is...WHY is oil not coming up around that shaft? You can tell the entire upper cavity is dryer than it should've been meaning no oil had been up there for a while. I have not pulled the oil filter cavity yet to see what that looks like. Does this engine have an oil pump? Can it be removed/tested/replaced WITHOUT splitting the cases? Obviously I'll need to pull the cylinder to find out if there is a lower passage blocked, which begs the question...if I have to pull the cylinder, should I replace it with the BIG BORE KIT? 

[Airbusboy 14]

I'm assuming the bottom end is SPLASH fed with oil so the crank/connecting rods should be okay? (yes, oil level was fine). 

[Fishfiles 20,145]

Did you or someone else change the oil and filter recently , or not recently for that matter ? 

[_Wilson_™ 6,563]

well fish, you nailed it. when was the last oil change ? if you away to take /post pics, or videos that would come in very handy. 

 

Edit: fish beat me to it. 

Edited December 31, 2020 by _Wilson_™

[Airbusboy 14]

Yeah guys...I'm kinda anal about the maintanence on this thing. Oil and filter was changed likely 6-7 times in it's short mileage life. And correction...it has 1370 miles on it. Any ideas as to WHY oil would not be getting up around that stud and into the upper end?  

[Airbusboy 14]

Could it be that on the last oil change the filter could've been installed in such a manner as to prevent oil from flowing, and thus creating my problem?  Is there any point on this motor where a gauge could be installed to SEE the oil pressure when it's running?

[_Wilson_™ 6,563]

oil filter in backwards is what I'm thinking, pull the filter cap, and check. 

[Fishfiles 20,145]

14 minutes ago, Airbusboy said:

Could it be that on the last oil change the filter could've been installed in such a manner as to prevent oil from flowing, and thus creating my problem?  Is there any point on this motor where a gauge could be installed to SEE the oil pressure when it's running?

Yes , it could be as simple as the oil filter was installed backwards last time the oil was changed ---but not as simple is  how much damage to the engine occur 

[Fishfiles 20,145]

Like Wilson said , pull the cover and see if it was installed backwards ---- when you remove the cover I would do it easy , so it does fall out and then you don't know if it was backwards or not , catch my drift 

[Airbusboy 14]

Okay. A few questions. 

1) What will I see when I pull the filter 'IF' it was installed backwards?

2) 'IF' it was installed backwards, could that have restricted the flow and caused my issue?

3) Does this engine have an oil pump that I should look at and evaluate?

4) Has anyone used the 'Big Bore Kit' with or without the new head? Is it any good?

5) Can the rocker shaft/rockers in that upper assembly be replaced seperately or is that a one-piece assembly? 

[Fishfiles 20,145]

Question 1)  usually there is writing on the filter  , unless it came from China which we have seen them marked wrong from who ever made them                             >>>>>  the hole end of the filter goes towards the cover , no hole end towards the spring

                 2)  yes , total blockage 

                 3) yes the engine " had " a oil pump ( before it was run with out oil ) if this is the case and how long it was run that way 

                 4) think you better find out if you have anything to put a 'BIG BORE KIT " on before thinking too far ahead 

                 5) rocker arms are available separately and still available for $60 each new , but go back to 4)

[Airbusboy 14]

Okay. ASSUMING I find the filter was in backwards (I'll check tomorrow), if I see no metal in the top end, and filtering the current oil I find no metal and do a flush or two with new oil/filter, is the bottom end splash-fed and would it be safe to assume the bottom end is good, then add new rocker assembly and new push rods and fire her up?  

[Airbusboy 14]

Assuming I go ahead and rebuild the top end...I'll need two rockers, one rocker shaft and two push rods, right? Anything else? Does that rocker shaft come out easily? 

[_Wilson_™ 6,563]

as fish said, how many long was it run like this ? ( if the filter is in backwards ) 

 

10 minutes ago, Airbusboy said:

would it be safe to assume the bottom end is good

 

i would say no, you know the top end took a hit, so i would check the oil, but my thinking is it's going to have metal in the oil which would do damage to to the bottom end. 

[Fishfiles 20,145]

Did you ever figure if the lack of oil is from a installed  back wards oil filter or a trashed oil pump yet ?

[Airbusboy 14]

I'll be pulling the filter in the morning to check for a reversed installation. How can I check the oil pump to see if it's working? Is it removable? The motor was not run long since it's last oil/filter change, maybe an hour or two. 

[shadetree 5,880]

start with checking to see if the oil filter was installed backwards ?, if it was ?, you may, or may not have engine damage ?, depends on how long you ran it this way ? ..IT DOES NOT TAKE BUT JUST A FEW MIN'S TO RUIN AN ENGINE IF NOT OIL IS FLOWING !!!.