Like 200i not starting

[Renee74]

Okay good I will try it again just to make sure and find a tester for the compression. Thanks for the info I was trying to find out what a good compression reading would be. I'll let you guys know how it goes.

[Renee74]

Hey guys sorry it took so long had to go back to my real job haha I did the compression test several times and I got nothing. Zero. I've been trying to do some more research maybe finding a new engine for it might be my best option. Any opinions or advice would be great.

[CROSSBOLT]

Zero is not possible! Well, it's UNLIKELY! However it fits with your video sound track that I heard.

So, now, we get to the WHY of no compression. What I would suggest is to remove the air cleaner cover and inspect the filter, the inside of the cover and inlet. All air passages clear from cover snout to throttle body? If yes, then next:

Remove the cam/valve cover, just like you would do to check/set the valves. You can then check:
1. Timing chain in place?
2. Timing of cam correct?
3. Any thing look alarming with cam lobes, bearings, rockers, valve stems, springs & keepers?

Report back you findings and we'll go from there.

[Renee74]

Yeah I tried it several times thinking I might have done something wrong but compression test is pretty straight forward and I got nothing. I'm just stumped at this point.

[Stig / Major Tom]

Finger in the spark plug hole, throttle wide open....hit starter. Nothing?
Husband was running on the highway, full throttle probably....how many miles - how many minutes at full song, with adequate oil level?

Before searching for a new engine....maybe remove the valve cover and turn engine over clockwise by hand with a 14mm socket in center of white fan.
Feel for compression with the spark plug in.
Chain in place?
Valves opening and closing?

Stig

[big blue]

Wow, NOTHING, yep I fully agree time to open the valve cover and check the top end.

[Renee74]

 Okay guys I couldn't really feel any compression when I did the finger test so I took the valve cover off and it seems like there is oil inside which I figured there would be a little but when I smelled it, it smelled like gas (might have been my hands from spark plug though) The chain does look to be in place and the valves do move up and down when turning the engine. The bottom valve does seem to be loose compared to the top. I made a quick video to show. 

[big blue]

That is a lot of movement the valves should be set at .004 in. at TDC. Check out this video on Youtube for the procedure...

[Renee74]

Thanks. I did find and watch the video while disassembling and thought the same thing. These valves are really loose. I was having a hard time adjusting them. I'll have to watch the video a few more times. Had to leave the garage because my old pup wanted to go outside.

[Stig / Major Tom]

When you get the piston to top-dead-center on the compression stroke there should be a tiny fraction of movement - how much? - less than millimeter.

YouTube of the valve process by a member.


Also, with the other markers - You may need to insert a straw into sparkplug hole to find the stroke to TDC properly.....

Get the valves adjusted - then we may have compression .

Stig

[big blue]

At least it's nice to see that there is oil in the valve cover and that the chain is still functioning.

[Renee74]

Thanks for all the advice guys. Also excellent video. I think I got the valves adjusted properly but I do have a question Stig about the TDC? What is the TDC? I know you said put a straw where the spark plug hole. Should I leave the spark plug out while doing that? 
Also Happy Father's Day to all the Dads out there! 

[Renee74]

Update after doing the valve adjustment and putting everything back together I tried turning the scooter on and it still sounds flooded so I took the spark plug out again and it wasn't as wet but did smell of fuel. I'm going to check the valves again just to be sure. ugh

[big blue]

TDC is top dead center it is the point on the COMPRESSION STROKE when the valves are both closed and the plug ignites the fuel charge. The piston can be up in the cylinder and NOT at TDC that would be the exhaust stroke. To tell whether you are at the right position the piston should be up AND both valves should have a little wiggle. On the exhaust stroke the exhaust valve will be compressed by the tappet. It is possible to be 180 degrees off even though the alignment holes on the cam sprocket are in position. BTW you do have the plug out when doing the straw thing.

[Renee74]

Thanks I'll give that a try. I am wondering though....if the starter motor is bad could that cause the scoot to have zero compression? Maybe a silly question but it did cross my mind.