Will IP shaft seal leak outside the pump?

[tonydca]

My L400 is bucking and chugging a bit on cold startups, and since I am unsure how many miles are on the original glowplugs, I am planning to go ahead and replace them.

But seeing recent posts about how the IP seals could be also be a potential source for startup problems reminded me of a comment I heard a while back.

Can't remember who it was from, but from somone purportedly "in the know".

Their comment was that if the IP seals are leaking, that fuel to a greater or lesser extent will be visible on the outside of the IP itself. So if a flashlight shone under the hood reveals a nice, dry, dusty IP, then all is well with it.

Can anyone here confirm or deny this rumour? Seems like a quick and cheap troubleshooting tip if it be true.

Tony.

[jessef]

You can check but by your description, the main shaft seal is letting in air overnight causing the rough starts. You can't see the front shaft seal as its behind/inside the timing case cover.

[tonydca]

Cheers for the info - good to know.

I think mine is the plugs, 'cuz she can sit for 3 days in my underground garage at 18 degC and start up fine first crank, but sit overnight outside when it is damp and cooler, and there is a consistent miss on what sounds like one or two cylinders for about the first 30 seconds, even if I cycle the key (glow cct) on and off 4 or 5 times before cranking.

In any case, it fires up first crank every time, there's just that annoying miss when it is cold.

[strada-caster]

mine's been doing the same thing...bumping and chuging on first start on the 'cold' mornings.

I figured it could be:
-glowplugs (multimeter says I got juice to all of them)
-IP seals (but it doesn't bump and chug during the summer)
-switch from summer to winter diesel at the pumps (anybody know when that happens?), assuming winter diesel is 'drier' allowing for less of a gelling effect in the cold.

a buddy of mine runs a f250 diesel and was stalling, and coughing and farting. This only started a little while ago, as soon as he added some lubricity formula to the tank, all was well. Upon the next fill up, it was coughing and stalling again.

After reading the first few posts, my engineering brain kicked in.
summer, the seals are warm enough(even if dry and old) to seal properly.
winter(cold), the seals are getting cold enough the shrink from the temperature alone, producing an air gap.


These same symptoms plagued me last winter, but I never did anything about it cus as soon as I got into second gear, all was fine and didn't do it again till the next cold morning start.

[strada-caster]

Update, I ran a little test this morning. put the block heater on for an hour.

It started soooooooo nice. Gonna do that test a few more times, one morning no heater, the next morning with heater...just to make sure this wasn't a wierd fluke of some sort.

anyways, that tells me that my IP seals are not letting air in. any new ideas?

tony, if you have a heater, try what I just did...see what results you get.

[tonydca]

I have an underground garage in my building; dry and 15-20 degC year-round.

It can sit there forever and start up perfect first crank every time.

But leave it out overnight cool and damp and 6 degC, and cougha-chuggga-farta, no matter how many times I cycle the glow plugs. It was fine over the summer, but with nights getting cooler, the prob is getting worse.

I'm 95% sure it is, like yours sounds like, an issue of being too cool for crappy glow plugs.

[strada-caster]

awesome, we got the same problem...one of us will get it fixed eventually and then voila.

hopefully I'll get my plugs out over the weekend and do a resistance test, and visual inspection...

[strada-caster]

Got the plugs out this weekend.

They seem fine, other than being all black. No white marks or severe heat lines. resistance was .6 - .7 ohms for all.

I did notice that a couple came out with what seemed to be oil, and I have noticed more black coming out of the tailpipe on acceleration. Could this be my rings going bad? I have 120,000 km's on the clock.

as far as I'm concerned, new glowplugs will not make a difference for me. Unless someone else knows better.

[tonydca]

Who makes the plugs you currently have?

On a number of online forums I have heard that NGK plugs model CY55 are the bees-knees for replacement for the 4M40.

I have heard also about NGK CY05 as being perhaps the Mitsubishi OEM plugs, even better, but I had a fellow in Japan look a Mitsu OEM set up for me and he claims Mitsu is charging him 31000+ Yen for a set (around $380CDN), so for 90 GBP off the 'Net (around $150) I'm gonna try a set of CY55's.

I mention this because a set of *new* HKT CP-05 plugs were absolute crap. They fit, "looked" and ohmmed-out fine, but I think they just didn't get hot enough, and I am running now on used NGK ones of unknown history.

The tips of HKT vs. NGK look very different; the HKT ones are fatter/stubbier, and the NGK ones have a slimmer tip to them.

[strada-caster]

The number is Y-115T1 (NGK Glow Plug, 12 Volt Silver Top, Not QGS) currently installed in my '92 4d56t.

Good to know that cp-05 are apparently crap, cuz I was looking at cp-06 for my replacements. shipped from australia were 60 bucks to my door for 4. I can only assume cp-05 are similar to cp-06 at this point in time. Not sure if they were HKT like you mentioned.

Well, let me know when you get them installed. hopefully they make a difference.

[strada-caster]

just found the following online http://www.ngkpartfinder.co.uk/partfinder.php

confirms my part number is correct.

It tells me your part no. is cy57(ceramic style) , maybe cy55 is correct, just not ceramic.....

[tonydca]

The website part finder does not show an entry for the L400 from Mitsubishi - L200 and L300 only. But I believe the Shogun is how the Pajero was badged in the UK.

At any rate, it comes up with the Shogun engine as a 4M40T (T for Turbodiesel) and CY55 as the plug number.

Good website, tho'!! Cheers,

Tony.

[strada-caster]

Tony,

do you have the new plugs yet??
any update on your situation?

[tonydca]

Tony,

do you have the new plugs yet??
any update on your situation?

Not yet, other than that removing the plugs and cleaning them + the bus bar didn't help. Too busy futzing around with wheels at the moment...

[TardisDeli]

Tony, did you check the big round metal relay, silver metal, shaped like a small girly size fist. I think its mounted near your hood hinge on L400. that controls whether your glow plugs turn on appropriately. If your power to your glow plugs is OK, and the load test on your battery is OK, then think relay.

Question: do you need to press the fuel pedal to get started? You shouldnt need to. Once you get started, does the coughing and bucking stop, if so I would suspect glow plugs more than IP. But if the bucking and black smoke continues once the engine is warm, then suspect IP Christine.