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Discussion Starter · #1 ·
Just bought a 2014 Honda Rancher 420 4x4 foot shift for $1400, shows close to 800 miles. The previous owner told me that it needed an injector, said it quit running so he took it to the dealer which did series of test like compression and other things and they told him it needed an injector. He broke the piece that the sits on top of the injector that the fuel line connects to, but did show me that the pump is pumping fuel to it. What is the best way to confirm that the injector is the problem? It is $60, so I don't just want to throw one at it blindly.
 

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With the injector removed and plugged in, the fuel line connected, the air temp sensor in the airbox plugged in, IACV etc. plugged in... crank the motor over and watch for a bit of fuel spray from the injector. You may have to crank it a bit to clear any air in the line & injector before you notice anything. If you can't connect the injector up properly while its out, you'll have to figure out a way to view fuel spray while its mounted in the throttle body.

If something is broken on it already (people break the connector or retainer at the line usually, because they won't read the service manual) you'll have to replace that part before you do anything else. You can get a service manual for that bike from the link I posted for you in your other thread. Keep us posted how its going if you can.
 

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Discussion Starter · #3 ·
Alright, got in the new parts, hooked up the old injector and fuel sprayed from it. But would not start, sounds like it just isn't getting quite enough fuel. So I hooked up the new one, same thing, checked spark, great spark, checked compression... 40 psi. Is that to low even to start? I had the exhaust unhooked from the head the other day and it was clean, didn't look like it had been previously using oil. And my gauge could be off to, old HB tester. What does it sound like to y'all?
 

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Discussion Starter · #4 ·
Put a little oil in the cylinder, showed over 60 compression. Put the plug back in, still would start. It's gotta be something else, what's the first thing to check?
 

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Put a little oil in the cylinder, showed over 60 compression. Put the plug back in, still would start. It's gotta be something else, what's the first thing to check?
Well, you've replaced the broken fuel injector. Are there any other broken or disconnected parts on it? All of the electric plugs must be in good condition and connected with sensors in place on the bike for the motor to start. That includes the airbox sensor... Use a new NGK spark plug properly gapped. If any wiring has been cobbled on it you'll need to replace the harness.

Compression should be 73 PSI at cranking speed on a warm motor. Either your gauge is junk, is leaking, or there is something wrong with the motor.

You'll have to read and follow service manual troubleshooting charts with a multimeter in hand to learn anymore about your bikes. Swapping in new parts that you don't need will empty your wallet quickly as you know... Enjoy your work!
 

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60 psi is low in my book, was this done with the throttle held wide open when cranking it over ?. if not ?..then that is how its done. if so ?, then you have a leaking tester ?, or worn top end.
 

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Discussion Starter · #7 ·
Yeah believe me I know. Been testing a few things and reading a lot in the manual, I pulled the injector back out to see how much fuel is spraying. With closed throttle, it shoots a good spray, but with the throttle open it doesn't spray anything. Is that normal!?
 

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Discussion Starter · #8 ·
Thanks for chiming in shade tree. Yes that's with throttle open. I have the parts to fix the top end if that's the problem, but like retro said, it gets expensive when you just start throwing parts at it. Plus, I've always thought that a worn top end would mean oil consumption, everything I've inspected show it to be a clean running engine. Just trying to rule out everything else.
 

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Discussion Starter · #9 ·
And something else with compression, if I put oil in the cylinder it shows over 60. I would think that would at least that would be enough to make it "pop" or something. But it changes nothing. Just so y'all know, I am here to learn. If anything I say isn't right please correct me, I've worked on a lot of Hondas put this fuel injection that I LOVE is killing me! Lol, help please?
 

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Have you tried starting fluid. If it won't try with that its not going to happen

The other thing I would do is put my hand on the exhaust and turn it over, same for the injector opening. Make sure it sucks and blows.
 

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Discussion Starter · #11 ·
Yeah with the last bit of a can, it didn't help. Just adjusted the valves, which was a little lose. Checked the compression again and only have barely over 30. About to pull the head off, facing the fact that it needs rings, if all goes well I will have it running today hopefully.
 

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Discussion Starter · #12 ·
Wait, it appears that the they changed the head in 2014, gonna have to order different gaskets and rings Oh well, I have plenty of others to work on but was hoping to have it out of the shop today! Thanks for all yalls input, I do believe low compression is my problem.
 

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It might be low but it should still run with that compression if it is getting fuel and spark.
I doubt very much 60 psi is good enough to run the motor ?, shoot...a trx300 needs at least 100 psi to run good.
 

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Thanks for chiming in shade tree. Yes that's with throttle open. I have the parts to fix the top end if that's the problem, but like retro said, it gets expensive when you just start throwing parts at it. Plus, I've always thought that a worn top end would mean oil consumption, everything I've inspected show it to be a clean running engine. Just trying to rule out everything else.
nope..just because the compression rings are bad ?, does not mean the oil rings are bad !. what this means is, it won't burn oil !. but it won't have enough compression to run if the compression rings are shot :).
 

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It might be low but it should still run with that compression if it is getting fuel and spark.


I doubt very much 60 psi is good enough to run the motor ?, shoot...a trx300 needs at least 100 psi to run good.


It has a decompression mechanism built into the cam, spec is only 73psi.....


Sent from my iPhone using Tapatalk
 

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OP, have you checked the timing ???, if it jumped time ?, this could be the reason your compression is low.
 

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It might be low but it should still run with that compression if it is getting fuel and spark.


I doubt very much 60 psi is good enough to run the motor ?, shoot...a trx300 needs at least 100 psi to run good.


It has a decompression mechanism built into the cam, spec is only 73psi.....


Sent from my iPhone using Tapatalk
ah..ok..i keep forgetting these newer motors run on less...thanks..but still..60 is still to low in my book.
 

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I doubt very much 60 psi is good enough to run the motor ?, shoot...a trx300 needs at least 100 psi to run good.






It has a decompression mechanism built into the cam, spec is only 73psi.....





Sent from my iPhone using Tapatalk


ah..ok..i keep forgetting these newer motors run on less...thanks..but still..60 is still to low in my book.


It is low there is no doubt about it, but it’s not as bad as having a motor that should read 150psi and you get 60 on your gauge lol


Sent from my iPhone using Tapatalk
 

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It has a decompression mechanism built into the cam, spec is only 73psi.....





Sent from my iPhone using Tapatalk


ah..ok..i keep forgetting these newer motors run on less...thanks..but still..60 is still to low in my book.


It is low there is no doubt about it, but it’s not as bad as having a motor that should read 150psi and you get 60 on your gauge lol


Sent from my iPhone using Tapatalk
welllllllllll duhhhhhhh..lmaooooooooo.
 
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