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Discussion Starter #1
Hopefully someone on here can help me. The previous owner of my 400 completely destroyed this engine. Not blown up but welded everything in the top end. So I rebuilt the top end. It cranks I have spark. It was blowing fuel out of the carburetor so thought it was out of time, I turned the time 180. Checked the oil pressure but once I got the oil cover off the oil filter was bone dry. Pulled all oil lines off blew threw them all clear besides the main line from the bottom of the oil tank was clogged. I’m thinking maybe the oil pump is bad. Once I opened the oil cover the one gear said out on it and the other said KCY. So if I’m correct those are correct? But at this point anything will help. I’ve spent so much time trying to think of anything else im
About to give up on it. Thank you.
 

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Pretty vague story; you rebuilt the top end - what does that mean? To some people putting in a new head gasket is rebuilding the top end.

So I'll presume you replace the cylinder and piston with a Chinese Niche brand. You got a new head, new cam, new rocker arms, new cam chain and new valves.

Now you can't be 180 degrees out of time. The ignition fires on every stroke (wasted spark ignition); it just doesn't have any fuel or compression on the exhaust stroke so nothing happens other than a spark.

At any rate you got it started and now you don,t have oil pressure - since you have the clutch cover off, remove the sump screen and clean it. Remove the oil pump, disassemble it, check the rotors for wear and clearance - the large side pumps the oil out of the motor under low pressure and the small side pumps oil out of the tank and into the engine under 'high' pressure (high pressure may be 4 psi - Honda does not have an oil pressure specification - the engine requires flow more so than pressure). You don't check for oil pressure, you check for flow.

Remove the strainer from the bottom of the oil tank and assure it is clear - remove the oil filter cover - put a quart of oil in the tank - the lower line of the oil tank goes to the lower fitting on the clutch cover. If you wait long enough even with the engine not running, oil will begin to flow out of the lower hole of the oil filter cavity.

Just check the connections and flow from tank to pump and flow from pump to filter and you should be good.

Oh, I forgot to mention - after inspecting the oil pump, pack the rotors full of petroleum jelly or other light grease to assure it primes when the engine is started.

Whew!
 

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Discussion Starter #3
Okay sorry I thought I put in there it doesn’t start. We cannot get the bike to start. That’s what brought me to believe I was not getting oil pressure. Or the filter was put in backwards. The filter was put in the right way but very dry. I’m having way to many issues with this bike. It’s kind of hard to pin point what to really say to you. I put in a brand new jug piston rings cylinder head and valves and seats that came with it when I got it I put a stage one hot cam in it new timing chain and gear a new clutch basket new wiring harness and ignition. I do have spark and it’s blowing fuel back out the carb so I figured it was getting fuel as well I bought a cheap compression tester but it says I have no compression I adjusted valves to spec and valves are moving just won’t fire. It came with the niche brand kit when I bought it.
 

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Now were getting somewhere - sounds like you have bent valves - how did you time the camshaft to the crankshaft during assembly?
 

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Discussion Starter #5
I brought the crankshaft up to where the t and the line was. And the cam gear lines lined up with the top of the cylinder head, with the cam lobes facing down. I can put a picture on here of it in a little bit if need be.?
 

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I don't use the T mark - use the piston - the piston needs to be at TDC when the cam sprocket is installed

If it were in my shop, I would lock the crankshaft near TDC of the compression stroke and apply 150 psi of air pressure to the cylinder to find out where the compression is going. Typical compression with the throttle held wise open is 120 to 150 within 5 compression strokes - anything less than 100 and it won't run.

BTW - oil pressure has nothing to do with whether it will start or not.
 
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