Outer Limits 4x4 Board

i need help. if you KNOW what you are talking about regarding diesels, not just what has worked for you, please read and tell me your thoughts!

i went to a "REPUTABLE" diesel workshop in bayswater, asked about putting more boost in my 89 gq 4.2 turbo diesel. it has an aftermarket denco system. the mech lifted the bonnet and straight away tells me that my patrol doesnt have a boost compensator. and further, that it would be this that ione of the problems with my vehicle, as the fuel wont adjust with the boost. he then takes me for a drive in it and says its very sluggish and this would be because of the lack of a compensator. he takes me back to the office and shows me some info that he wrote and was published in a 4x4 mag. he also said that the tappets were noisy and the injectors needed to be done. (even though the guy i bought it off 2 years ago, is a diesel mech and he said he did the injectors just before selling to me) so all up, for injectors, fit boost compensator, increase boost to 10psi, and "tune for 10psi" i was quoted $2650. then that night i went to the berrimah diesel, diesel myths web-page and they state that you dont need one, and that there is very minimal gains to be had for spending $1000-$1800 on a compensator. they say it can be tuned without the compensator. i also read a comment that said if a compensator was needed, then why dont denco, mtx etc fit one as part of their package?

So.............. do i need to go spend the $2650 and have it done by them, or..... should i fit a boost guage, egt and manual boost controller then have it "tuned" (fuel matched to egt) on a dyno and that willl be fine?

please help as the $2650 can be spent elsewhere if its not a necesasary job!

thanks guys!

go else where.
aneroids arent nesesary. but do help. they are definatly not worth any where near that money.

for less than that price i got a rebuilt gu pump with bigger internals, aneroid, brand new injectors and a dyno tune.

lack of a aneroid wont make the car sluggish in most instances. but will improve econamy and lower smoke emissions before boost.

being sluggish is more to do with tune or condition of pump/injectors or turbo

im not a pro but i can gaurentee you that the prices you are being quoted are too high even if the injectors are stuffed.

Dieseltec off this forum would be the guy to chat to, his is generally very happy to reply to questions and pm's

The cost price on a compensator is about $700 + fitting. A Compensator is not going to rectify your vehicle being sluggish on take off, off boost. The compensator removes fuel when the boost is low while the turbo spools. The turbo will actually spool faster with fuel added as the extra fuel generates extra heat and exhaust gas density, on the down side there can be excessive smoke and EGT's. The guy is probably quoting on a rebuild of your pump plus a compensator, most diesel shops are very careful about running the pumps on the test bed and bringing them back to factory spec before undertaking any modification. I you havent had the pump checked and injectors reco'd in the last 150 k klms it would be where to start as adding fuel through knackered injectors or low or varying output pump can lead to problems through poor fuel atomization.

Joel

let me guess, they gave you the full workshop tour, told u he is on the "diesel fitters association gig" etc etc showed you all their machines, then hit you with some fuckin stupid out of this planet price?

$2,650 is probably made up of the following items;

Injecters $700
Compensator suppply & fit $1,200
Dyno and tune $700

Above prices are not necessarily the best value for money.

Tha being that said we do not run a boost compensator, the down side of such is the black cloud of smoke at 1500rpm under noise, but in a comp car who cares.....

On the road if you are not heavy on the foot at take off you will not have the black smoke.

Leagally you should have a compensator fitted to comply with ADR 30 Diesel smoke emissions. But this is generally not enforcd at this stage.

Jason

First of all, check all the basics first. Air and fuel filter condition, valve clearances, inj pump timing, test the injectors, if you said they have been done they may still be ok. If anything is in need of attention then do it, then run it up on a dyno and see where your boost is set to, see what emmissions are like.

As PGS said a boost compensater does that, it alters the fuel delivery according to boost pressure, giving you three points to independantly adjust fuel without altering the others.

To run say 12-14psi of boost and have good power in that range you need to be able to have fuel there. However down low in the rev range with lower boost you will have too much. Most turbo kit manufacturers only run around 7-10psi, hence no reason for a boost compensater required. If you want a lot of boost you will have to fit a b/comp. As you said, fit a boost and egt gauge, check all your basics and dyno it, it may be all you need.

Or you may need more, but doing the above is the first step. Any questions call me Andy: 03 9739 5031

thanks heaps guys! you have been a real help!!!!

bogged - how did you know. i think i saw every piece of machineary in the place, and how they worked. then was shown dyno read outs + an article he had written for a mag!

full-boost wrote:thanks heaps guys! you have been a real help!!!!

bogged - how did you know. i think i saw every piece of machineary in the place, and how they worked. then was shown dyno read outs + an article he had written for a mag!

I've had the royal tour and they attempted the same reamign on myself.. laughed at the bloke and walked out, went elsewhere.

Give Andy a call at Diesel Tech in Lilydale - just had my GU done by him, and his persistance and skills are fuckin stunning. Im VERY happy... would recommend him anyday.

Bogged,

thanks very much, I am very happy you trusted me do do your vehicle and then let me find your problem.

Andy

Dzltec wrote:Bogged,

thanks very much, I am very happy you trusted me do do your vehicle and then let me find your problem.

Andy

Now, how about another 20-30kw?

Gee the exact same story I got from them! My truck was getting a bit hot and a little sluggish I thought, went to see the gurus your talking about walked in they popped the bonnet yep no anaroid, you need your fuel pump rebuilt and new injectors took it for a drive and said how sluggish it is then said, now when do you want to book it in! Was quoted about $2700 from these blokes.

So not happy with that went home rang bazzle said where I'd been he said let me guess fuel pump rebuild injectors and an anaroid! Same shit story they tell everyone. So went out changed the fuel and air filters and heaps better. Then rang a bloke in Bayswater called bayswater fleet maintenance he has a dyno, booked it in just told him it was getting hot and not sure of the problem. So a phone call at midday and the nice bloke says yep no problems its doing 500 on the pyro, pumping out 85rwk and the reason its getting hot is cause the clutch fan is RS! What about the pump I say he says not its fine, looks like its been off before and rebuilt as its all painted up like when they do them! So after spending $95 bucks for the dyno and a new clutch fan I was most impressed and would never go back to those idiots down the road who try and rip people off all the time.

My 2c worth! :-)

sorry to hijack but while the Diesel Guru's are here i would like to pick your brains.

First off, can a GU TD42 Injector pump be put on a GQ engine from 1992? i know they are both TD42's but is there a huge diff in the pumps that would prevent them from being able to be installed

2nd how can you tell when your diesel pump is getting on? dunno if its been done or not in my car prior to buying it, no leaks or that, just want to know if there are any tell tail signs of it wearing down?

lastly, since installing a safari snorkle my engine temp rises quite a bit going up hill. it gets to about 2/3 on steep climbs. could it be over fueling and not getting enough air?

can't help on the fuel pump fittment but most places when modding or repairing pumps mark what they have played with.... i.e yellow or red paint pen

all td42 pumps fit all td42 engines that Ive fitted

My GQ,

yes it will bolt up, only diff are to do with calibration. Later vehicles have diff advance and fuel delivery specs.

One tell tale sign is if you remove your outlet/ leakoff/ return line banjo bolt from the top of the pump, it may have black oil on it. TD42 pumps have a weakness in the front seal and over time suck in small amounts of engine oil into the pump. Other signs can be excessive smoke, sluggishness, hard to start, as long as all other areas have been looked at first, then you may have a pump problem.

Injector pumps life is determined by fuel filter changes and fuel quality.

Andy

While we're on the subject of Turbo's, what is a safe maximum boost on a 4.2TDI. Mine is a 2005 coil cab ute (37,000k's). It has a shortened standard exhaust with a straight through muffler & the boost compensator has been adjusted (by a diesel fitter) to allow more fuel down low. It has a good quality boost adjuster on it and is currently running 12lb boost with great results. It also has 285/75-16 Muddies on it. I have just bought a 3" dump pipe and will have the rest of the 3" system made up soon. I will have it dynoed after the 3" system is on to see where it is at.

Cheers....................Pete!

Dzltec wrote:My GQ,

yes it will bolt up, only diff are to do with calibration. Later vehicles have diff advance and fuel delivery specs.

One tell tale sign is if you remove your outlet/ leakoff/ return line banjo bolt from the top of the pump, it may have black oil on it. TD42 pumps have a weakness in the front seal and over time suck in small amounts of engine oil into the pump. Other signs can be excessive smoke, sluggishness, hard to start, as long as all other areas have been looked at first, then you may have a pump problem.

Injector pumps life is determined by fuel filter changes and fuel quality.

Andy

Thanks so much

I have the oppitunity to get a GU pump for my NA TD42 92 model, so i might take that offer up (engine died, but pump was done 50,000 ago.

As for my engine its not sluggish, starts very easy (less than 1 crank and its going) and its not smoking at all

12 psi is about as far as you want to go to be really safe, you can go up to 14 on the standard GU turbo, after that you are just creating hot air.


If you are dynoing it, make sure they check exhaust temps and not with an infa red thermometer, these arent accurate enough, fit a pyro.


Andy

hi andy, how do i get in contact with you? where are you?

thanks!

Im in lilydale, our business is called Diesel-Tec, phone is 9739 5031, address is Fact 10 east crt, Lilydale industrial park, lilydale, melways 38 e2.

Andy

Thanks for the advice Andy. I played with the boost for a while until i got what i thought was a comfortable setting without, as you say, creating a lot of hot air. 11-12 seemed like the best compromise. I plan to fit a pyro gauge to it to monitor temp! Would the dump pipe be a good place to put the sensor??? I can tap the hole before i put the dump pipe on to make it easier, that's all.

Cheers.....................Pete!

Thats the most practical place, but not the ideal. It really should be pre turbo, but a lot of work to do it.

Egt's not to go over 550c at the dump pipe.

Andy

What about temps before the turbo, so exhaust manifold pre-turbo?

X2

Thanks Andy. Can you recommend a good pyro gauge as i have never bought one before.

Cheers....................Pete!

I just brought a VDO pyro guage and probe off ebay, heres the link:
I brought mine from these guys, really good to deal with.
http://cgi.ebay.com.au/SIEMENS-VDO-EXHA ... dZViewItem

Theres also this one on there at the moment, looks the same as what I have got:
http://cgi.ebay.com.au/siemens-VDO-pyro ... dZViewItem

Cheers, Beretts

its aford not a nissan wrote:X2

that would make it up to 1200 Dgrees, are you sure?

txhog wrote:

its aford not a nissan wrote:X2

that would make it up to 1200 Dgrees, are you sure?

Are you kidding or serious question?

He meant he also wants to know. Cheers, Beretts

Thanks guys, jeez they don't miss ya do they! Expensive little suckers....................Pete!

Gruntahunta wrote:Thanks guys, jeez they don't miss ya do they! Expensive little suckers....................Pete!

Yeah but worth it to know how hot it's gettin.