B engine compression & leakage testing along with glowplug & injector replacement

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Sep 3, 2007
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Okay folks. The weather here is lousy and has been like that for weeks on end now. It just won't stop raining and its freezing cold to boot. So I thought I'd start a thread here that I'll add to (as I go) over the next month or whatever.
I've been intending to fit new glow plugs and reconditioned injectors as part of "routine maintenance" on my 2977cc B diesel. It has done 240,000kms without ever having the head off and with nothing more than regular oil and filter changes and a couple of tappet checks/adjustments. What's more, I've owned it for the last 27 years so I know it has always been maintained regularly and has never suffered any overheating dramas.
As far as I can tell, it starts and runs now in exactly the same way (if not better) as it did when I first bought it back in 1981. But then of course wear causes very subtle changes and also spreads them out over a long length of time. - So I am no doubt talking sh#t here. - It is quite possible that it is slightly more rattly and smokey but I just haven't noticed. (But I don't think so.) However I will concede that I do get an annoying "whiff" from the blowby pipe occasionally. And this is particularly likely straight after I've done an oil change. I suspect it has something to do with "gases/fumes coming off virgin oil" as it is heated for the first time but then again - I'm probably talking dribble. It is rather a sickly/unpleasant smell. But I never notice it while driving. Only when the engine is idling and there is very little wind around (and as I say - usually only after an oil change too).
Anyway - I thought it would be a good to go really "anal" here (cos I'm good at that) and record lot of figures/statistics - Even going so far as to do things like measuring the idling rpms before and after fitting the reconditioned injectors. And perhaps even taking a video of "before" and "after" to see if there is any difference in engine sound.

Edit 7 September - Forgot to mention "oil usage" which is relevant here. I've never noticed any change in this over the last 27 years. I have always been able to go from one oil change to the next (traditionally - 7000kms) without topping up the oil inbetween. However - It is usually about 1 liter (1 quart) low at that oil-change stage so I occasionally top it up by this amount (if I notice it is low) prior to changing the oil. This has got a bit more complicated recently though because I'm not covering much mileage. Nowadays I'm changing the oil annually with as little as 2000km travelled - So now I certainly don't ever need to top up between changes.

So I've started by getting the gear ready to do the compression and leakage testing.

I'd like to thank Amaurer for his thread that got me interested in the HarborFreight (made-in-China) stuff. I landed both their compression tester and leakage tester here in NZ (I seem to remember I ordered it from California) for just $150NZ while an inferior leakage testing set by itself (which appears to be made by the same Chinese manufacturer but without a branding name) retails here for $300!

The HarborFreight gear is not anywhere near the standard of the "Snap-On" brand but I could never justify buying that. (About $800NZ for the leakage tester alone?) And I believe the HF gear will be entirely adequate (read "accurate enough") for the limited use it will get from me and probably better than the average standard of most tools/equipment sold in this country (where you have to really search to find quality). Crikey - I'll probably use it only this once!
Anyway - Photos:
Here the fancy advertising cardboard they came in:

HarborFreight01.webp

And here are the sturdy plastic cases:

HarborFreight02.webp

And here is the compression tester (The fitting with the blue zip-tie is the one that matches my glowplug sizing):

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And here is the leakage tester sitting inside its box:

HarborFreight04.webp

First I had to decide which "leakage testing fitting" to "bastardise" so I could connect into my diesel's cylinders via the glow plug hole. (Unlike the compression tester, the leakage tester wasn't designed specifically for diesels - So it didn't come with an approriate fitting.)

Here's a photo of the two fittings that were supplied alongside the spark plug from my :princess:'s car. (Hey - I wonder when I last changed those plugs?) This enabled me to choose the smaller fitting on the left (with the O-ring removed) for "bastardisation". (It is not really logical though - because I doubt I'll ever bother doing a leakage test on her car with the other fitting:D):

HarborFreight05.webp

And here is how I got the threaded part that I wanted from an old glowplug:

HarborFreight05A.webp
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HarborFreight05A.webp
 
This is the part I will use:

HarborFreight05B.webp

And here is that part with the glowplug it was derived from on its left and the fitting it will be mated to on its right:

HarborFreight06.webp

And this is a trick I often use to enable something like this to be held in the jaws of a 3-jaw chuck - Wrap it in masking tape:

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HarborFreight05B.webp
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I needed to take some measurements of course:

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And then "turn off" the thread:

HarborFreight09.webp

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HarborFreight08.webp
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HarborFreight10.webp
 
Hey. Look what happened when I removed the tape! I think their chroming department needs a bit of "quality control" (but it certainly doesn't worry me and this was the only fitting where the chrome looked really dodgy to start with):

HarborFreight11.webp

Here are the two components pressed together (with some silver brazing flux brushed in there beforehand to assist the "Easyflo alloy" to enter the joint by capillary-action):

HarborFreight12.webp

And here it is cleaned up a bit and ready for brazing:

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HarborFreight12.webp
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The brazing in progress using silver brazing alloy (Easyflo) and an oxyacetylene torch:

HarborFreight14.webp

Before the flux has been chipped/washed off:

HarborFreight15.webp

And afterwards:

HarborFreight16.webp

Righty ho. That's that little part of the job done.

And already I've thrown in heaps of posts/photos yet I haven't even started doing any of the tests or replacements! (That will come as I get around to it in the coming days/weeks.)

By the way - I've never liked the idea of "compression testing" because the results you achieve depend so much on how fast your starter motor is turning over your engine. That's why I think "leakage testing" is the "way of the future".
HarborFreight14.webp
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Yep, This is gonna get interesting and should be saved as Tech item or something? Best regards "Mate"
 
Watching with interest.:)
 
Lostmarbles,
Was there any reason why you went with the analog v. digital compression tester?
 
Lostmarbles,
Was there any reason why you went with the analog v. digital compression tester?

Price was the determining factor for choosing what I got.

But having said that - I'd probably still prefer analog over digital - but it may have something to do with my age :D

(Hope I haven't set peoples' expectations too high here with this thread. And I really had to start it now because otherwise, once I start recording stuff, the job will start getting too awkward. -- It's a bit like my preference for doing a "rolling restoration" rather than an "all-out body-off restoration". By the way - The day's fine at the moment but I'm roped into gardening work by the Mrs. --- I know - I'm under the thumb and down-trodden!)
 
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Hi folks. --- Had a bit of time to muck around on the cruiser today.

When I changed the fuel filter a month or so ago I up-ended the old cartridge into a bowl to see if there was anything interesting in there. And I found a big globule of rusty water:crybaby:. So I've been meaning to remove the drain plug on the fuel tank (which I do periodically) to drain any cr#p out.

That's the first thing I did today.

The plug came out easily using simply a 1/2" square drive ratchet in the hole:

Drain1.webp

But I found no rusty water - or anything else to be alarmed about - in the bottom of my tank (:hhmm: Perhaps the rusty water in the filter was from the filter-manufacturer?):

Drain2.webp

Incidentally - I try to keep the fuel tank fairly full when the vehicle is sitting around unused. The idea behind this is that there will be less air in the tank from which condensation can form. (Cos I believe condensation is mainly responsible for water sitting in the bottom of people's tanks. And this water of course causes rust there.)
Drain1.webp
Drain2.webp
 
I expect you'd already know about the "bottle of meths" trick to dewater your tank?
I suppose it's only useful if you're giving it enough use to fully drain the tank after adding the meths.
 
Now - back onto the topic of glowplugs.

Here's a photo of all the plugs varieties that have ever been fitted to my BJ40.

Glow01.webp

On the left is the ex-factory plug. In the middle is a Toyota supplied replacement that was fitted on 19 February 1998 @ 186,008kms. And on the right is the plug type that I am fitting now.

An annoying feature of the later substitute plugs is that the terminal thread size is smaller. Because of this I had to make new plastic caps for them.

The resistance figures are innaccurate. I measured these values with my cheap ohmeter and the FSM says their resistance should actually be 0.2 ohm!

And here is a page from the manual showing that the glow time is meant to be about 20 seconds and that they reckon my 12V cruiser should draw around 10.3 Amps for glowing. (Funny - I always assumed to would be something like 20 amps at least!)

Edit Nov 09 - The FSM figure is a "per plug" figure. So the total glow current would be up to 41.2 amperes for my 4 cylinder diesel according to the FSM.
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Now at this point I took note of the performance of the glowplugs that were already fitted. - The middle type in the post above (Nippondenso - supplied by Toyota)

My thermometer says 13 oC is 55 oF:

Glow03.webp

At 13 oC it took 15 seconds till I could see that there was definitely some "glowing" occuring in the "controller" and by the time 30 seconds was up, it was glowing like this:

glow2.webp
Glow03.webp
glow2.webp
 
Now my glowplugs are wired up like this:

glowwiring.webp

So I took some voltage measurements with the old nippondenso plugs before the new HKT ones go in.

I decided to take all measurement at the glow relay and found the following while the controller was glowing orange:

At G: 10.4V
Between G and S: 2.4V
At S: 8.4V
(PS. These figures are a bit different from those I obtained last month when doing almost the same tests. which proves there are lots of variables operating here.)

Here's a photo of my meter measuring between G and S to get the voltage drop across the controller:

GlowbetweenS&G03.webp

I also measured the resistance between G and earth: 0.6 ohms

Based on this, theoretically my glow current should be 10.4 divided by 0.6 which equals 17 amperes!
glowwiring.webp
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Here's something from the FSM that shows the expected glowplug resistance reading (that my measurement didn't entirely agree with):

FSMspec.webp

And here is how the voltage measurements were taken at the "glow relay" which sits behind the big plastic air duct in the passenger footwell area:

Glowrelay02.webp

It is interesting that, unlike spark plugs, glowplugs have no sealing washers of any sort. You just screw out the old - and screw in the new. And you don't seem to get any leakage issues!

Here a photo of removing the busbar:

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Glow06.webp
 
I expect you'd already know about the "bottle of meths" trick to dewater your tank?
I suppose it's only useful if you're giving it enough use to fully drain the tank after adding the meths.

Thanks Dougal. Yeah. I've heard about it but never done it.

I'm driving up to Kaitaia (and beyond probably) this November (plus going down to Picton a couple of times soon) so at least I'll get to cover a bit of mileage in the coming months.

But my wife and youngest son argue about who has to sit in the back - I think they both prefer us to take the #%&&$## car to go away in!!!!:D

(At least the Picton trips are by myself - but then that's not exactly far!)
 
And here's a photo of the busbar removed:

Glow02A.webp

I understand the "vertical" nature of most if this busbar is specific to B-diesels (and not shared by the 3B) - or am I wrong here?

Of course I used an air gun to clear crud away from the glowplugs before removing them:

Glow03A.webp

And I used a long-reach socket to remove the old plugs and reinsert the new ones:

Glow03B.webp

(Actually the socket I used was 1/2" AF because I couldn't find any long-reach metric ones around.)
Glow02A.webp
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