1380 Woes, a bit long
Turbo Mini Forums

Been a while since ive posted here, though been lurking!! need a bit of help if poss guys..

Heres the story……. (bear with me please, this is the cut down version!!!)

I built an engine for the estate last year, a 1380 with SW5 cam, AE Pistons, ported head, center main etc (the usual deal) with the intent on having a good solid reliable engine with a fair bit of poke, not a road racer as it a family car! Anyway, the first main trip after running in was on the riv-un 2006. When I got there, as it was the first long run, about 400odd miles, I decided to check out the plugs etc. #4 plug had signs of what I can only describe as “crusty deposits”. I thought maybe it was a dodgy plug, so after a couple of days bought a new set of plugs, a few days later and the same “crustyness” again, so I then renewed the leads, rotor and dizzy cap. ( I bought 2 different sets of plugs, different temperature ones), No joy!

Once home, it was still happening., always #4 plug. Left it for a fair few months hoping it may sort itself out, it didn’t, decided the engine had a duff ring or summat, and planned to build a new engine..

By Christmas, I had built a new bottom end, new block, new pistons, this time Hypatec ones, basically a completely new bottom end, including gearbox as well (I was only planning on keeping cam and then the head upwards.) this was swapped over the Christmas break. The dizzy was also swapped completely as the curve wasn’t quite right for what I wanted (and one of the threads was stripped)

After a few days of running in I took it for a tune to get it basically setup, and found out that the carb jet was causing odd fueling problems (after replacing the fuel pump for an electric one!) and was duly replaced with a complete freshly rebuilt carb.

A few more weeks and I thought I better check out the plugs again… I bit the bullet and pulled them out, guess what! Noticeable discoloration on #4 plug! ARSE!

This then lead me to think that it’s the head…. As it’s the only bit left from the original engine. So, I set about building a new head, this time with new guides, seals, valves, the works!

Took the head off for swapping over a couple of weeks ago, and #4 plug was a lot darker than the others, and chamber looks a bit on the oily side. Refitted new head, and again replaced the leads, plugs, dizzy cap and rotor arm, and just for good measure, swapped the coil too..

Started driving and feels much better driving, so thought I may have fixed the problem…..

2 days ago, I checked the plugs,,,,, and its happening again! 3 look like new, #4 doesn’t!

I don’t know what to do….. apart from cry! Someone help me! Please!

Pics below are as follows:

1) Current plugs, only done 500 miles tops with new head
2) Head i removed
3) #4 plug and chamber
4) #1 plug and chamber

if you need any other pics, shout!

Cheers
Ross.

Edited by mini-marauder on 21st Apr, 2007.

Sooperdooperturbocooperexpertengineering!

Hi,
Are you using the heater take off at the no4 end of the head?
Cheers,
Gavin :)

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pop off the rocker box ,and turn over the engine and measure full lift of each rocker ,see what you get , maybe you have a worn cam ,reducing duration and lift on that cyl . the other thing is ,how are your breathers running ,and also is the dipstick for the block the right one .could the sump be overfull ?
regards robert

Medusa + injection = too much torque for the dyno ..https://youtu.be/qg5o0_tJxYM

oh and check for bent pushrods !

Medusa + injection = too much torque for the dyno ..https://youtu.be/qg5o0_tJxYM

It dont look too bad. No4 gets hotter so use the heater take off as Bat says, but then run it in and go to rolling road.
Is cam timing spot on?
Paul

I seriously doubt it!

Certainly seen worse!

I always run the water take off at #4 end even if it just goes straight back to the water hoses, helps keep that end a little happier

Every day is a school day ...........

How fast and how expensive ...... the same question...

i have to say that although i've seen a-series get hot at no4 end i've never seen them get that hot as to discolour the plug in the mileage you state (not to that extent). What water pump and pulley are you using?

I've seen the future and tbh its Pie

thats i bit of oil burn which can make it go that colour but personally if the car drives well and is reliable then leave alone, my 1380 number 2 was always slightly different colour to the rest and was never a problem.

always looking for them bigger bunches of bannanas

Thanks for the replies guys, to try and answer a few questions...

i am running a heater take off at that end, the later type with inline tap and larger tubing. the hole in the head was drilled and enlarged as big as it would go, has been on both heads.

Cam was a brand new SW5 and has done it since day 1, but i will investigate the lift when i get chance.

all breaters vent to air and are not routed back into the carb if thats what you mean.

pushrods have been replaced during the saga!

engine tune should be OK as it was only a couple of months since the last RR at Southam mini and metro.

Water pump is deep impeller type (new) and using normal pulley.

Dipstick is std A+, and is in an A+ lump so that should be fine.

have been thinking it was oil being burned, but on 2 completely different engines on the same cylinder is really bad luck! ?!?!

Cheers

Ross.

i keep thinking oil,

Sooperdooperturbocooperexpertengineering!

yes mate looks like but dont worry about it, if it goes well and has good readings from the rollers then leave well alone, also tyry a leak down test that will give you a good idea

always looking for them bigger bunches of bannanas

hoggys right but... i would also like to add

a suspect cam which has not been machined accuratley duration and lift

i think this is the case

crazy off the wall question but is ure oil preasure ok ? the reason i ask, is when i bored out my race stuff to use 73.5mm pistons number 4 pot can occasionally create very small pin holes into the gallery (this is rare, but it is in the vizzard book and it happened to me) the hole usually appears near the bottom of the pot and allows oil to squirt in...

just a thought...probably wrong but hey it is late :)

Richie

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a good way to check the cam in a bit more detail , is to get the inlet and exhaust both open the same amount on cyl4 and see how far open they are ,then compare that with the same test done on other cylinders .
i had my first grind done for the mini in 98 ,and it was fouind to be 14 degrees out ,!! so it can happen ,no dont ask !

Medusa + injection = too much torque for the dyno ..https://youtu.be/qg5o0_tJxYM

Edited by Sprocket on 23rd Apr, 2007.

yes i know but just wondered if it was possible for it to still oil up a plug ? just shooting ideas as all.

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BENROSS...MINIMARK..WOLFIE (comic genius).....CARL....MARTPAUL.......AXEL
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