No compression!!

[fordrangerracer]

I have a 200x that I just put an XR200 cam and head on. The orginal cam was very worn and the exhaust valve was bent. I had the valve relief cuts cut down a little deeper. There is absolutely no compression. I'm out of ideas on this thing!!!!

[pipeline triker]

Sounds like it might be out of time and a valve is open at the wrong time. Were the valves seated nice and did they have a good sound when you tapped them down with a hammer to check there return, after the springs were installed. You say you had the valve releifs cut deeper what kind of a lapp did you, to make sure they are seated all the way.

[fordrangerracer]

I think it's out of time but I have the marks lined up exactly. I jumped a tooth ahead and got more compression but I don't think it will run like that. As for the head I just bought one off of eBay and it seems good And I took the piston to the local atv shop and they just cut the groves deeper. I'm out of ideas!!

[fordrangerracer]

I'm going to throw the 200x valve cover on and put a new head gasket on just to try. I'm just lost on timing!! I cand figure it out. What if maybe I time it 180 off???

[trike savior]

you say you had the valve seats cut. did you add shim underneath valve spring to hold valves closed properly? turn head upside down and pour fuel into combustion chamber, it should hold fuel. if not there is your problem

[yaegerb]

Here's a good article on setting your timing.

http://www.3wheelerworld.com/showthread.php/141964-HOW-TO-Set-timing-on-Honda-185-200-motors-with-pics

[manbearpig]

this same thing happened to me when i installed a 200x cam in my 185S

the dimensions of the xr200 cam are different than the 200x cam. the xr200 cam is larger and if you left the rocker adjusters set for the 200x cam, it'll hold the valves open all the time and you wont have compression.

SIMPLE SOLUTION!!!

just adjust the valves to the xr200 cam. make sure you read that thread about setting your timing, get it all set, and then adjust the valves and youre good to go... assuming you dont have valve seat damage

[fordrangerracer]

I didn't have the valve seats cut just the reliefs recut on the piston. It is properly timed and valves are properly adjusted. The head doesn't have any leaks and rings and piston are all but brand new.

[trike savior]

you need my favorite test. it sounds like you still have motor still assembled.

get a compression tester that has a hose that detatches from gauge. on plug end of hose will be Schrader valve (like in a tire valve stem) remove it. thread hose into head and instead of attatching compression gauge, hook it up to air compressor.

you will either need to remove cam gear bolts or hold it on top dead center at crank bolt with a non ratcheting breaker bar. idea is to have valves closed.

then just listen for air escaping from intake, exhaust or crankcase. you will hear some from crankcase getting around rings but a lot from crankcase means bad piston . I know you don't think that a possibility but if you cut larger valve reliefs in piston it could have cut too thin and developed crack or hole in piston. other wise you will find air in intake or exaust ports indicating bad valve. or air escaping at head gasket

[trike savior]

oh and it is easier to do this with compressor with storage tank. let it air up completely then unplug it so you do not have background noise. and if you have a regulator on it turn it down to 20 psi. that's all you need for air leak to be audible

[yaegerb]

I didn't have the valve seats cut just the reliefs recut on the piston. It is properly timed and valves are properly adjusted. The head doesn't have any leaks and rings and piston are all but brand new.

Well, then it should have compression, but it doesn't which means something is incorrect. One of the following will be your culprit....Valve clearance too small (manbearpig already made a reference to adjust the valves according to xr200 OEM specs), valve stuck open, worn cylinder or rings, damaged cylinder head gasket or improper timing (I posted a really good step by step article earlier).

[fordrangerracer]

Put gas in the combustion chamber didn't leak at all just evaporated. It holds air. I'm lost!!!

[trike savior]

wait how did you do both of those tests? one is engine assembled and the other disassembled. the fuel in combustion chamber test is with head off bike and upside down. fuel wont just evaporate that takes a few minutes. if it went away quickly it should have come running out of intake/exaust ports

[fordrangerracer]

Lol took it apart and did the fuel test. It was sitting for a while and I was watching it. Put it back together then did the air test I honestly don't understand. Rechecked the piston no holes or cracks. Rechecked the rings and they're all good. Am I just fighting a lost cause here?

[trike savior]

all i can say then is your timing is off. you have to be holding a valve open when the piston comes up on top dead center. are you using the 2oox cam gear with the xr 200 parts. all i can think is that the orientation of the xr200 cam with the cam gear bolts may be different from 200x parts. what i would do is remove rocker caps and put a screw driver down the spark plug hole. be careful not to let screwdriver bind while doing this. use a wrench on the crank to rotate engine and watch what the valves are doing when the engine is moved. use the movement of screwdriver as a guide of where the piston is (ie top dead center). make sure each valve is opening when it is supposed to and that you have play on rocker arms when at tdc on compression stroke. try this through a couple cycles and see if you can find something

[Flossyb20]

...did you put the spark plug back in? I've done it before....:naughty:

[fordrangerracer]

Lol yes I've forgot the plug before!!! I returned the XR cam and just ordered an OE XL185S/XL200R cam. I'm actually very embarrassed to tell you all this. But honestly I had absolutely no idea that the rings couldn't be in line with each other...

[fordrangerracer]

All the compression was sneaking in between the ring gap and the cylinder... lol

[barnett468]

Hello fordrangerracer

Your right that is kinda funny but only because it is on a bike and not a car motor, lot's more work and lot's less humor there. Don't worry you are not the first one ...... You can download free service manuals on line, member kbonly has a very good link and there is another.

I or someone else can post them if you want.

[fordrangerracer]

I'm sorry for this again put the carb is blowing tons of air out. I don't even háve the air box on. Bad valves?

[trike savior]

check timing and valve clearance

[barnett468]

Hello Fordrangerracer


I copied the posts below just so I could follow them on one page. I’m sensing that you are getting frustrated and impatient, it is easy to miss things when this happens. Your problem has already most likely been answered in one or more of the xlnt posts you have received, so we just need to find out which one it is..

I would do the following in the following order at this point, others might not.



TESTS TO PERFORM


1.VALVE CLEARANCE - Remove carb, rotate motor till cam lobes face down, check valve clearance. Did it tighten up?

2. VALVE LEAKS - Remove carb and with valve clearance set to your CAM’s specs or slightly LARGER, spray CARB cleaner into intake hole [not brake cleaner] or pour in some gas.

3. If it disappeared within 10 seconds or less your intake valve is bent or stuck open. If it is NOT then do the same thing with the exhaust.

4. If there are no leaks proceed to the next step. If there are well then you know what to do.

5. TIMING – look at previously posted link. Flywheel mark on T in screw hole, both cam lobes down, check valve clearance. Did it tighten up to 0 somehow? Adjust valves to your cam’s specs or slightly LOOSER.



QUESTIONS - I have a few questions if you don’t mind.


What do you mean by “ it blows air back thru carb”? It will a little anyway due to valve timing events so a little is normal?

Does it “FEEL” like it has “STRONG” compression?

Did you install new cam, I assume so?

Are you using the “good” ebay head?

Can you do a compression test?

Have you tried to start it?

Does it run?

Does it have spark?



PREVIOUS POSTS


I didn't have the valve seats cut just the reliefs recut on the piston. It is properly timed and valves are properly adjusted. The head doesn't have any leaks and rings and piston are all but brand new.


I think it's out of time but I have the marks lined up exactly. I jumped a tooth ahead and got more compression but I don't think it will run like that. As for the head I just bought one off of eBay and it seems good And I took the piston to the local atv shop and they just cut the groves deeper. I'm out of ideas!!


you say you had the valve seats cut. did you add shim underneath valve spring to hold valves closed properly? turn head upside down and pour fuel into combustion chamber, it should hold fuel. if not there is your problem


Put gas in the combustion chamber didn't leak at all just evaporated. It holds air. I'm lost!!!


wait how did you do both of those tests? one is engine assembled and the other disassembled. the fuel in combustion chamber test is with head off bike and upside down. fuel wont just evaporate that takes a few minutes. if it went away quickly it should have come running out of intake/exaust ports


Lol took it apart and did the fuel test. It was sitting for a while and I was watching it. Put it back together then did the air test I honestly don't understand. Rechecked the piston no holes or cracks. Rechecked the rings and they're all good. Am I just fighting a lost cause here?


I'm sorry for this again put the carb is blowing tons of air out. I don't even háve the air box on. Bad valves?


check timing and valve clearance


Hope this helps.

[fordrangerracer]

I rechecked timing, dead on. Rechecked valves, dead on. I even turned the adjusters out all the way. There is a ton of air bring pushed out of the carb. About the same amount coming out of the exhaust. I ordered another head off of a wrecked trike so at least I know it was running when tore apart.

[fordrangerracer]

I installed an oem cam. There is not much compression it does have spark but not enough compression to run.

[barnett468]

Hello Fordrangerracer


Ok, thanks for the info however there is no mention of the "spray carb cleaner in port" test I suggested, so I can only “guess” you did not do it. This means that someone as well as I will have to guess at your problem if they chose to offer any more suggestions.

If you don’t do all the tests requested no one can ever offer you informed suggestions, which doesn’t help you as much as if you did the tests and posted the information.

Based upon everyone’s posts my guess is that you either may not have done the previous gas test that trike savior suggested properly and/or you misinterpreted If in fact this is what happened then the tests results you acquired are could be incorrect. This is why I suggested you do it again.

About how long did you let the gas sit in the head, 2 minutes, 5, 15 etc?

Your valves are in fact leaking irregardless of whether they do not look like they could be to you when you viewed them with the head off. There is now no other possible conclusion. It’s your choice whether to believe it or not.

You said you bought the head off ebay probably with no warranty. What did you expect? Now you are going to buy another one off ebay. Sorry but I don’t understand that logic. I personally would just properly repair the one I have if possible instead of possibly playing Russian Roulette with ebay heads. What is the seller’s feedback rating? What was the ad description ie good used, rebuilt, etc?

xxxx

you say you had the valve seats cut. did you add shim underneath valve spring to hold valves closed properly? turn head upside down and pour fuel into combustion chamber, it should hold fuel. if not there is your problem

The head doesn't have any leaks and rings and piston are all but brand new.

xxxx

get a compression tester that has a hose that detatches from gauge. on plug end of hose will be Schrader valve (like in a tire valve stem) remove it. thread hose into head and instead of attatching compression gauge, hook it up to air compressor.

I didn't have the valve seats cut just the reliefs recut on the piston. It is properly timed and valves are properly adjusted. The head doesn't have any leaks and rings and piston are all but brand new.

xxxx

Well, then it should have compression, but it doesn't which means something is incorrect. One of the following will be your culprit....Valve clearance too small (manbearpig already made a reference to adjust the valves according to xr200 OEM specs), valve stuck open, worn cylinder or rings, damaged cylinder head gasket or improper timing (I posted a really good step by step article earlier).

xxxx

Put gas in the combustion chamber didn't leak at all just evaporated. It holds air.

fuel wont just evaporate that takes a few minutes. if it went away quickly it should have come running out of intake/exaust ports

xxxx

Lol took it apart and did the fuel test. It was sitting for a while and I was watching it.

All the compression was sneaking in between the ring gap and the cylinder... lol

xxxx

I'm sorry for this again put the carb is blowing tons of air out. I don't even háve the air box on. Bad valves?

Your problem has already most likely been answered in one or more of the xlnt posts you have received, so we just need to find out which one it is..

I would do the following in the following order at this point, others might not.


1.VALVE CLEARANCE - Remove carb, rotate motor till cam lobes face down, check valve clearance. Did it tighten up?

2. VALVE LEAKS - Remove carb and with valve clearance set to your CAM’s specs or slightly LARGER, spray CARB cleaner into intake hole [not brake cleaner] or pour in some gas.

3. If it disappeared within 10 seconds or less your intake valve is bent or stuck open. If it is NOT then do the same thing with the exhaust.

4. If there are no leaks proceed to the next step. If there are well then you know what to do.

5. TIMING – look at previously posted link. Flywheel mark on T in screw hole, both cam lobes down, check valve clearance. Did it tighten up to 0 somehow? Adjust valves to your cam’s specs or slightly LOOSER.

I rechecked timing, dead on. Rechecked valves, dead on. I even turned the adjusters out all the way. There is a ton of air bring pushed out of the carb. About the same amount coming out of the exhaust. I installed an oem cam. There is not much compression it does have spark but not enough compression to run.

xxxx

I ordered another head off of a wrecked trike so at least I know it was running when tore apart.


Hope this info helps.

[yaegerb]

if you think your head is toast, I have a 200x head in good condition that I will part with. Send me a PM if you are interested.

[tripledog]

This is a very educational thread, and I am glad I found it. I am going to use this procedure, but I think I will use a hardwood dowel instead of a screwdriver to find TDC. Less chance of making a foo - foo; at least as I see it.

[barnett468]

Hello tripledog

You can always find tdc on the piston simply by lining up the timnng marks on the flywheel or locating the T in the timing window. If you use a dowel you can put a couple different colored marks on it to watch but that's excessive for most purposes.

[trike savior]

I just use something in the cylinder as a visual aid because it is easier when you are watching the valves on top end to have piston reference right there instead of constantly looking down at flywheel. this has helped me quickly find cams off a tooth and 180* wrong many times.

ranger racer. sounds like head your using has bad valve seats. do that fuel test in combustion chamber again