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Discussion Starter · #1 · (Edited)
i pulled my plugs this morning to have a look and give them a quick clean/gapping as i have a dyno day tomorrow (decided thats the only thing i was going to do to prepare). anyway most of my plugs were fine and looked like this (yes iridium is a waste of $$$ i know):


http://i299.photobucket.com/albums/mm284/stoker100/P130309_103001.jpg
http://i299.photobucket.com/albums/mm284/stoker100/P130309_1049.jpg

now cyl #6 plug looks like this (any idea what would cause this?) some of the buildup was quite solid and couldnt be removed with a wire brush i had to needle file it off:


its been about 4 years since ive changed plugs so ill be getting NKG V powers in the near future. yes ive been burning some oil, sometimes it doesnt burn any for 6 months then it burns lots for 3 months. now im assuming if the plug is gunked up the head will be gunked a little also, ive wanted to run seafoam through it but theres no retailers for it in Australia so ill have to find something else to use (suggestions please)

oh, and thats not crap from the spark plug well! i made this to clean the wells before removing the plugs (just to make sure no crud gets in there):


anywho wish me the best of luck for tomorrow im hoping to get over 125wkw (167whp), last time i went on the rollers was 2.5 years ago (i got 117wkw, 156whp).
http://members.optusnet.com.au/dstojko/dyno10th6th06.jpg

At the time i was running the ZE with a DE EPROM with ZE VRIS points tuned and nothing else, now ive added since then a 2.5" catback exhaust, 65mm TB, MSD and a full KL31 EPROM. While im not expecting much i think those mods would be good for 8wkw fingers crossed.

ill also be doing a little tuning during the runs, as some may know ive finished my tuning software (for now), i can modify the rev limiters, VRIS, fuel enrichment and timing maps while the car is running on the stock ECU heres a few pics:

http://i299.photobucket.com/albums/mm284/stoker100/probetune/loadaddress34b.jpg
http://i299.photobucket.com/albums/mm284/stoker100/probetune/loadaddress34c.jpg
http://i299.photobucket.com/albums/mm284/stoker100/probetune/loadaddress34e.jpg
 

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im loving the spark well cleaner.

any details on what sort of cruid it was on the plug? whether it was a carbon based build up or a metal one or what not?
 

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Discussion Starter · #3 ·
it was covered in oil on the top, beneath that was a dark white powder fused to the sides of the tip, not sure how else to explain it. when i filed the lumps down it came off like a powder, similar to the whitish powder on the other plugs but a lot more of it.

im thinking tomorrow morning if i get time before the dyno ill warm the car up, get my carby cleaner can out and hook that up with a splitter to the vac nipple on the #6 intake runner (the nipple for the FPR), give it some gas and spray away, hopefully it should remove some deposits then ill have to pull the plug again and clean that.

on a side note i just found the receipt for the engine swap, it was done 22/10/04 so its coming up on 5 years now. the plugs were purchased 26/9/05 so they're getting pretty old now. man i keep too many receipts!
 

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hey cant wait to see how u go on the dyno! im going for one myself on wed just for the hell of it lol.
no idea what that is on ur plug tho :shrug: hope u work it all out :tup:
 

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how did the dyno run go? jmoore and me have been meaning to do a semi comparo between the probator chip and the one you did for j, im expecting, from what ive felt from being in the cars im expecting some good numbers from yours :)
 

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Discussion Starter · #6 ·
the dyno run went, well bad. i got 101wkw, the car drives great down low but has not much up top. i changed the plugs yesterday and it made no difference to performance, im going to test fuel pressure and compression today if i get time.

edit, as for the tuning, well obviously i didnt do anything after the first run as i knew something was wrong.
 

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oil build up - with contamination - two things - timming on the one plug off and obviously it's they cylidner with the oil sealing problem - my guess valve stem seal
 

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Or it could just be that is 4 years old.

Compression test should definately be done. How do you think I felt, I made 20 more kw then that, with boost.... Doing much better on a DE now with good compression.

Cylinder 6 ring is rooted?

Also that is heaps nice tuning software, way prettier then MegaSquirt interface.
 

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Discussion Starter · #10 ·
doing a compression test tonight, the plug leads measured fine, the cap and rotor are fine and after changing the plugs cyl#6 looks the same as the rest. i think the plug looked bad because it was just old and cyl#6 probably cops the most crud from the crankcase ventilation system. ill post back tonight with comp results and possibly if i get time ill check the timing also.
 

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Discussion Starter · #11 ·
magnacore KV95's probably getting on 4 years old now, resistance:
1- 8.92K
2- 4.27k
3- 8.48k
4- 3.77k
5- 9.43k
6- 3.97k

Ok, its been a long afternoon (4hrs after work searching for problems), here's what i got compression wise:

1- 208psi
2- 210psi
3- 208psi
4- 210psi
5- 209psi
6- 205psi

So im happy the numbers are good (done with no plugs in, no fuel or spark, took approx 5 cranks to reach max compression, first crank usually got it to 100psi) really put my mind to ease the engines ok.

As for my last post about the plugs being the same, upon closer inspection plug 6 is fouling again, the tip is fine but the white part around the electrode is blacker then the other plugs already, not sure why or how but ill get back to that problem later. pic:
http://i299.photobucket.com/albums/m...100/plugsa.jpg

The timing was a bit of a pain (getting the covers/wheel off etc) i set TDC it as mentioned above, TDC on the crank then the disty rotor to face cyl#1 firing point on the cap. Things i noticed were, the rear bank has the mark near the firewall side and 2 notches on top about 10mm apart, well my cam mark was near the firewall position but there were no other marks at the top (looking at haynes theirs had 2 marks to line up with with the notches and i didnt).

the front bank appears to be off (clockwise to the notch) about 4-5mm but it may just be the angle i was looking from, anyone know how many mm it would be off if it was 1 tooth off? (how far apart are the timing belt teeth?) i also noticed the rotor was past cyl#1 heading towards cyl #2's firing point. i would have assumed it would be dead on at TDC or slightly before if anything which is another reason for me to believe the timing is off. front bank (take into account the camera angle makes it look a little worse):
Image hosting, free photo sharing & video sharing at Photobucket
Image hosting, free photo sharing & video sharing at Photobucket

and the rotor position @ TDC:
Image hosting, free photo sharing & video sharing at Photobucket

Im assuming from what others have posted that my front bank is indeed 1 tooth off which will cause a power loss so ill probably pay someone to fix it up as i dont really have the time lately.

The last 2 things i saw was after checking the car was ok by starting it after everything was back together i had a loud noise coming from the timing belt (it used to make the noise a lot of i hadnt driven the car for a day or more) now im assuming its the belt or something hitting the cover. the last thing i noticed was the FPR sat at about 35PSI after i turned the car off and didnt really drop.

can someone please comment on the novel ive just written?
 

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No idea about the rest of the mumbo jumbo, but even those numbers for the leads seem reasonable, change em. 4 years is a long time.

Good compression numbers, congrats :).

You asked for a response, thats all ive got.
 

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from what you have described, it sounds as if your timing is off.

and the variation in those leads is a little suspect, if i had a spare set of leads id send them to you steve (i melted a set of probe addiction leads so no spare ones)
 

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Discussion Starter · #14 ·
thanks for the offer, ive got a spare set of old leads i can swap over if need be, the resistance should be approx 2.2k per foot so i would say theyre getting a little on the high side. not really concerned about the leads at this point in time, the fuel pressure and mechanical timing are the most important to me right now.
 

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Discussion Starter · #15 ·
well i have good news and bad news, the good news is just now pulling the covers off i found the timing is indeed CORRECT, it must have just been the angle before and i should have taken the cover off properly in the first place. DOH.

the bad news is that means im back to square 1, im going to go back and change my ECU back to the DE one and see how that goes, if that makes no difference ill go out and get a FPR and pray its all in the fuel.

one thing thats unexplained is the fact when at TDC the rotor button is between cyl#1 and cyl#2 firing points on the cap. i would have assumed it would be dead on cyl#1 or slightly earlier if anything. AAARGH!
 

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Discussion Starter · #16 ·
well today i checked the fuel pressure return line (with compressed air) seemed a little restrictive but ok (like last time), i then replaced the FPR and there was no change meaning it must be either the high flow fuel pump or a restriction in the fuel return line, i even checked the fuel pressure gauge with a compressor and its dead on.

ive given up for today, tomorrow im going to my mates to put it on some ramps and have a look at the line underneath or remove the return line and run it into a separate tank.

i havent swapped the ecu back to the DE as i shipped it out and am waiting to get it back still.
 
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