Running Problems.....please help me!

B

BoNgO

Active Member
Joined
Oct 23, 2008
Messages
2
Reaction score
0
Hello All,

Just joined this forum as i've just bought an '87 ZL400. I really like the Eliminator, my uncle had this one with running problems so he sold it to me for £200. The bike looks in great condition.

It will start on the button, run for about 10 mins with the Revs 'seeking' then it gets lumpy and dies. My uncle figured it to be fuel or electrical related. Possibly pulse unit or pick up coils.

Took it to a mechanic, he says it's the head gasket, but nobody before noticed and mixing fluids. He also says the compression in the cylinders is around 30psi.

I'm not sure if the guy's just trying to rip me off. I'm wondering if this is a common problem of the ZL. I'm also wondering where the best place for parts is.

I need help, suggestion and information. I hope you can help me become a 'Riding' member of the ZL fan club - as opposed to a hopeful watcher!


Thanks for reading and i look forward to hearing from you.

Be Lucky
 
Welcome Bongo!
The zl400 is one of the rarest of the zl's There isn't a enough info here on the zl400 yet to find any common problems. You will find alot in common with the zl600 which is more popular. If they said it has a bad head gasket then lets hope they did a leak-down test on the cylinders? Sounds like a vacuum leak to me

Enjoy the site! We glad you found us! :biggrin:
 
Dont trust the mechanics in the shops, I have seen them fix so many things that didnt need fixing and never actually get the real problem. Is there water in the oil? is there oil in the water? Did the bike get overheated? I have only seen 1 zl anything that actually blew a head gasget in over 20 years. Also not exactly sure about the 400 but everytime I tried a compression check on a zl900 with only one plug removed I got a false low reading! If I pull all 4 plugs then check the readings have been within specs even on bikes with high miles.

Vacume leak and or lean condition would be my first guess.
 
welcome bongo,sorry i don't know much about the zl400 but for service parts and coils go to this link,i use these for some of my zl900 parts (uk)

http://shop.wemoto.com/index.dyn?oid=1914478

if you need a new aftermarket exhaust system for the zl400 go to this link (cost abit though!)

http://www.predatorexhaust.co.uk/un...oad-Stainless-Steel-SYSTEM-BSI-E11-MARKED/955

have you checked the spark plugs because they can tell you alot! you need to check the oil yourself to see if there is any mixing then you can confirm the head gasket.if you can get the manaul for the bike it should have the base settings in it for the testing of the coils and pickups, look on ebay for a manaul.the first place i would start is the plugs and then the oil.if they are all ok check all of your electric connections.hope this helps.
 
Wow guys, thanks for the swift reply!

I'm gonna pick her up next week and try out your suggestions. I'm glad i found you!

I'm also having difficulty sourcing a Manual for the bike. An essential item for a beginner like me! Any ideas?

nice nice
 
By the way WELCOME to ZL-OA
A great bunch of people and lots of combined know-how. As Well some of the most Dedicated ZL Nuts I ever seen
 
The first thing I would do is start and run the bike with the gas cap open. If it continuosly runs in this mode then you have a clogged vent in the gas line. I don't know about the 400 but the 600 has a small plastic filter in the gas cap that is very easy to remove. It is about 3/8 of an inch around and fits under the cap. take it out and throw it away if the bike runs without it.
 
Welcome Bongo - I have yet to find a manual for the ZL400, I just use the ZL600 manual just about everything is the same anyway. You can check for water in the oil pretty easily just start the bike let it run for a bit then shut it off/ let it die, then look in the oil window if the oil appears milky/frothy then you can be sure there is water in it...

Good Luck
 
not sure about the 400 or 600 but my 900 I almost pulled the head off because I did the compression test wrong....this is what Kaw says for the 900..

With bike warmed up (I know yours doesnt run long, but try to get it other than bone cold), remove all 4 plugs, disable ignition..Put tester in one of the spark plug holes and crank the engine while you have the throttle WIDE OPEN..., then do each cylinder and compare...Usually a head gasket will affect one cylnder or two (side by side cylinders)...Make sure you have throttle wide open or you will not get enough air drawn in to compress (this will give all cylinders a low reading)...

If you have 3 cylinders at 120 psi and the 4th is at 60 then you have a problem with that cylinder...Could be head gasket, could be rings, could be valves....if you have 2 cylinders side by side low, you likely have a head gasket bad between the two cylinders...

I would bet it is a fuel problem....venting, or plugged screen or dirty carbs...

Willy
 
hey i used to have a zl400 before and it had serious overheating problems. sometimes water in the oil doe snot happen. try to run your bike for a while and see if there is any type of smoke coming from the exhausts, if there is white smoke then it is burning coolant/water. my oil was always clear but water somehow still got burned up and through the exhausts.

drain your cooling system after flushing it a few times and then fill and run your bike for a while. drain coolant and check it, if its murky/smokey/rainbowy then it looks like water is getting or combustion is getting somewhere its not suppose to.

do the simple things first buddy. remember to check venting and claen the carbs if you can. would be wonderful to find out if its just a little problem!
 
zub said:
hey i used to have a zl400 before and it had serious overheating problems. sometimes water in the oil doe snot happen. try to run your bike for a while and see if there is any type of smoke coming from the exhausts, if there is white smoke then it is burning coolant/water. my oil was always clear but water somehow still got burned up and through the exhausts.

drain your cooling system after flushing it a few times and then fill and run your bike for a while. drain coolant and check it, if its murky/smokey/rainbowy then it looks like water is getting or combustion is getting somewhere its not suppose to.

do the simple things first buddy. remember to check venting and claen the carbs if you can. would be wonderful to find out if its just a little problem!
Click to expand...

One question? Even with the overheating it would still run smooth correct?
 
yup as smooth as a baby's bottom, and still pulled like a train. its just when you stopped at the traffic lights when hot bioling water starts to pour out the overflow tube!
 
zub said:
yup as smooth as a baby's bottom, and still pulled like a train. its just when you stopped at the traffic lights when hot bioling water starts to pour out the overflow tube!
Click to expand...

What I am pointing out is that even if his head gasget was bad his engine wouldnt be hunting for rpm, and would most likely run smooth but push some type of steam, water vapor in exhaust, water in oil or oil in water ect. But the symptoms he is reporting has not given any sign of overheating as of yet.

So my next question is why does his mechanic think his head gasget is bad?
If the engine is hunting or running lean it will run hot, but should not run that hot to confuse the symptoms with a blown head gasget?

If he has a blown head gasget at all then I would think he has some dirt in pilot jets and or has some type of vacume leak as well, but at his description of the symptoms I would think its the carbs/vacume and the mechanic just wants to make a ton of cash for nothing, or might even think he can push him into a new bike if its a dealership.
Ever see that one tell you its gonna cost a fortune to fix then try and sell you a new machine instead? Its a win win for them! If you buy a new bike they make a ton of $$ and if you have the bike fixed by them they clean the carbs let the bike sit for a week or two and charge for a head gasget that wasnt done? Or worse yet they replace the head gasget and give you back a bike that still doesnt run right?

As well if its a blown head gasget what caused it to begin with?

Zub did you ever find out what was wrong? Was it a head gasget? cracked/warped head? or acracked cyl block? that was letting the water into the chamber and do you know what the official cause of the overheating was to begin with?
 
Last edited:
unfortunatley i never got to the bottom of it. cash was tight and i was young so i sold the bike on (wish i had'nt!). i think most likely it was a warped head or cracked cyl block tbh.
 
You must log in or register to reply here.
Back
Top