Suzuki Central Forum banner

1 - 20 of 20 Posts

·
Registered
Joined
·
13 Posts
Discussion Starter #1
Hello you guys new here first post but here's what's going on I have a 2003 kfx 400 same as ltz 400 as you all know. I bought it not running .So figured out my cam was my problem the engine wouldn't turn over. Re did all the gaskets lower and I per heads clutch water pump stator cover all of it. I did check my connecting rod its in spec. My piston is also but my rings are .5 below spec but the quad still turned on after it was all said and done. Compression was at like 105. But the quad ran for all about 4min now to my problem which is that my oil is milky but coolant is exactly where it should be. This is after the rebuild I did on it. I did find my petcock to be on prime so now I'm thinking maybe it's not oil mixed with water but with gas? Also a line that goes to breather to the tube on the air filter was not on straight but curved so no circulation could go through ? Also I opened the oil dipstick and it all came gushing out
 

·
Super Moderator
Joined
·
4,813 Posts
I would drain and refill the oil a few times to see if it is residual from the rebuild. Just run it a minute or 2 between flushes to circulate a little, but not get fully warm.
 

·
Registered
Joined
·
179 Posts
If you just did a rebuild, It could just be coolent from where you separated cylinder from the bottom end. I would change the oil and check it again. 2.2Qts of oil is all you need. I have rebuild a few of the ltz motors and when its a fresh build the oil will drain out milky from everything wearing in like the rings and stuff and all the assembly lube.

Your compression sounds a low at 105psi. Should be around 142psi on a warm motor. I see where you said your cam was a problem, you didn't have a bent valve did you?
 

·
Registered
Joined
·
13 Posts
Discussion Starter #4
Thanks for the reply's!
I am going to refill tonight and try to see. Is it possible it might be ? I was having start problems so also got a new carb and pet **** but I doubt it's that that's mixing would be more black then brown oil correct?
I would drain and refill the oil a few times to see if it is residual from the rebuild. Just run it a minute or 2 between flushes to circulate a little, but not get fully warm.
no bent valves but I did lap them and put new valve seals in as well. Sounds wierd for it to be really milky from just breaking in
Also would like to add when I drained the oil it was more then 2.2 qt I might have added a total of 3, the exhaust part where it comes out by the head was also smoking when I did have it on for the couple of min it was on
If you just did a rebuild, It could just be coolent from where you separated cylinder from the bottom end. I would change the oil and check it again. 2.2Qts of oil is all you need. I have rebuild a few of the ltz motors and when its a fresh build the oil will drain out milky from everything wearing in like the rings and stuff and all the assembly lube.

Your compression sounds a low at 105psi. Should be around 142psi on a warm motor. I see where you said your cam was a problem, you didn't have a bent valve did you?
 

·
Super Moderator
Joined
·
4,813 Posts
You could tell if it was fuel by the smell. If it continues to be that color, I would suspect a head gasket or water pump seal.
 

·
Registered
Joined
·
179 Posts
I agree it could be a head gasket or pump seal. I would lean more with a head gasket sense you have lower compression and your oil tank had pressure on it. I mean that hose you mentioned, saying it had no circulation, I wouldn't think it would create that much pressure, but then again anything is possible. Fix that hose and put fresh oil and go from there.
 

·
Registered
Joined
·
13 Posts
Discussion Starter #8
You could tell if it was fuel by the smell. If it continues to be that color, I would suspect a head gasket or water pump seal.
So I added new oil started it up had to use carb cleaner no knocks and no smoke out tail pipe but smoke was coming outta here
Right where it connect to head
49839
 

·
Registered
Joined
·
13 Posts
Discussion Starter #9
I agree it could be a head gasket or pump seal. I would lean more with a head gasket sense you have lower compression and your oil tank had pressure on it. I mean that hose you mentioned, saying it had no circulation, I wouldn't think it would create that much pressure, but then again anything is possible. Fix that hose and put fresh oil and go from there.
So I rechecked everything new oil that hose the carb and ram it for 2 min with thumb on throttle or else it will die. Oil looks okay this time still getting that smoke by head and header also rechecked compression and it's at 70 to be exact and spark plug was black also I want to add like I said I re did all gaskets except anything to do with piston but that wouldn't have anything to do with water and oil mixing it would just be low compression correct? Also did torque everything to spec head at 44 I belive no idea what to do now
 

·
Registered
Joined
·
378 Posts
If Piston is good I would put a new set of rings in and gap them to spec, Scuff cylinder before reassembly at 70 PSI I am surprised it is even running, are you sure your gauge is correct and that you are testing correct?
 

·
Super Moderator
Joined
·
4,813 Posts
Those rings are done. I’m a little unclear on whether you replaced the head gasket or not.
 

·
Registered
Joined
·
13 Posts
Discussion Starter #12
If Piston is good I would put a new set of rings in and gap them to spec, Scuff cylinder before reassembly at 70 PSI I am surprised it is even running, are you sure your gauge is correct and that you are testing correct?
Yes I tested it 3 times and got 70 72 readings. What should I scuff it with?
 

·
Registered
Joined
·
13 Posts
Discussion Starter #13
Those rings are done. I’m a little unclear on whether you replaced the head gasket or not.
Yea I did replace base and top gasket with new ones. I think with my original milky problem it didn't show with the second oil change but will try again
I did do a leak down test and only air comes out of the bottom hole by where you see if it's top dead center (so could be the rings)and it's not leaking horribly but it is. Intake and exhaust don't seem to be leaking at all
 

·
Super Moderator
Joined
·
4,813 Posts
Sounds like you’ve found your answer: blow by from the rings pressurizing the case.
 

·
Registered
Joined
·
179 Posts
Yup the leak down test is correct. Those rings are done for. And like jetmech25 said its blow by and its pressured your case. Get you a new piston and ring kit or go a little extra and get you a Big Bore kit. Either way you'll need to scuff or hone that cylinder jug and new rings.

Break in with some cheap conventional oil after a couple heat cycles, change it , again with cheap conventional oil, ride it for a couple hours and then change oil again. That way will let your new rings seat in correctly. If you use a good synthetic oil for brake in, it may cause the cylinder jug to be to slick and not let the rings seat properly.

BTW I subscribed to your YT channel.
 
  • Like
Reactions: JOE G

·
Registered
Joined
·
13 Posts
Discussion Starter #17
Yup the leak down test is correct. Those rings are done for. And like jetmech25 said its blow by and its pressured your case. Get you a new piston and ring kit or go a little extra and get you a Big Bore kit. Either way you'll need to scuff or hone that cylinder jug and new rings.

Break in with some cheap conventional oil after a couple heat cycles, change it , again with cheap conventional oil, ride it for a couple hours and then change oil again. That way will let your new rings seat in correctly. If you use a good synthetic oil for brake in, it may cause the cylinder jug to be to slick and not let the rings seat properly.

Okay so new piston and rings
Scuff or hone jug
New gaskets
Use conventional oil for break in? What kind do you recomend?

BTW I subscribed to your YT channel.
 

·
Registered
Joined
·
13 Posts
Discussion Starter #18
Yup the leak down test is correct. Those rings are done for. And like jetmech25 said its blow by and its pressured your case. Get you a new piston and ring kit or go a little extra and get you a Big Bore kit. Either way you'll need to scuff or hone that cylinder jug and new rings.

Break in with some cheap conventional oil after a couple heat cycles, change it , again with cheap conventional oil, ride it for a couple hours and then change oil again. That way will let your new rings seat in correctly. If you use a good synthetic oil for brake in, it may cause the cylinder jug to be to slick and not let the rings seat properly.
Also thanks for the sub! I appreciate your guys is feed back!!
BTW I subscribed to your YT channel.
 

·
Registered
Joined
·
179 Posts
I just use whatever house brand the part store offers. Aslong as it meets the specs of oil that you can use. I use carquest 10w40 but I switch over to Mobile 1 Racing 4T 10w40 after break in.
 
  • Like
Reactions: JOE G

·
Super Moderator
Joined
·
4,813 Posts
A light hone with a Flex-hone using a crosshatch pattern can work great, just make sure you don’t go through the Nikasil coating.
 
1 - 20 of 20 Posts
Top