1hdft pump tuning

[Lexie]

Any tips or advise on the above. Iv adjusted the screw on top of diaphram 1 and a half turns.

I dont want to tamper too much till i get an EGT gauge and boost gauge

Tia..

 

[Towpack]

http://www.lcool.org/technical/80_series/1hdft_pump_adj.html

The BCCT adjustment is the one where you really need the EGT gauge. If you attempt the last adjustment (BC Profile) be careful not to lift the diaphragm too far as the pin will be very difficult to get back in.

 

[Lexie]

http://www.lcool.org/technical/80_series/1hdft_pump_adj.html

Yeah thats 1 iv booked marked. Is 1 and half turns too much? It made very little difference, some say the msin fuel screw needs an 8th turn aswell

 

[Lexie]

Have you got your tuned? A little more go go on low rpms would make life here in the hills so much easier.

 

[Towpack]

I did the tweaks and it made a useful difference. The turbo starts producing boost earlier in the range than it did prior to adjustments. I can get EGTs on the limit so didn’t touch the main fuel screw. More fuelling will need an intercooler. Can’t remember how many turns I gave the off boost volume screw. Like the article says it’s just trial an error.

 

[hopeless wanderer]

Any tips or advise on the above. Iv adjusted the screw on top of diaphram 1 and a half turns.

I dont want to tamper too much till i get an EGT gauge and boost gauge

Tia..

This is the definitive guide in my opinion:
https://landcruiserclub.net/community/threads/fuel-pump-tuning-debunked.147905/

 

[Firewout]

be careful not to lift the diaphragm too far as the pin will be very difficult to get back in.

Of course exactly what I did ...
Don't worry, just grind the bottom of the pin on an angle so it pushes the lever sideways when you insert it again. I would do that anyway because when you start tweaking you'll want to see if the pin sits at the correct height. Also on mud some useful threads.

 

[Beau]

There's also a lot of info on tuning these pumps on the Ih8mud forum - Diesel section

 

[Lexie]

I did the tweaks and it made a useful difference. The turbo starts producing boost earlier in the range than it did prior to adjustments. I can get EGTs on the limit so didn’t touch the main fuel screw. More fuelling will need an intercooler. Can’t remember how many turns I gave the off boost volume screw. Like the article says it’s just trial an error.

How much is too much tho am scared with no egt gauge

 

[hopeless wanderer]

How much is too much tho am scared with no egt gauge

I wouldn’t chance the “wind it up till you see smoke and then wind it down a touch” I read an article by an Aussie tuner and you can apparently still get critically high egts without smoke in some conditions.

 

[Towpack]

I wouldn’t chance the “wind it up till you see smoke and then wind it down a touch” I read an article by an Aussie tuner and you can apparently still get critically high egts without smoke in some conditions.

+1.

 

[nielsc]

On the FT you can place EGT probe in the EGR blanking plate. Super easy this way. Mine hardly goes over 550 celsius PRE turbo , 1 bar boost and big intercooler and it goes quite good, minor smoke on full load.

 

[Shayne]

The way i see it is power is produced by efficiency so overfueling will sap power , so if you increase boost alone she will run lean and be down on power . So if you then nudge up the fuel screw in small increments - go for a drive power increase should be noticeable .

I did this on my 90 many times until i felt no improvement so turned the last nudge up down again , drove for a week to get used to things then nudged it up a little again and the improvement while slight was noted and so i accepted it was running at the most "efficient" burn i could hope for without fancy test equipment and left it at that .

A clean burn to avoid excessive heat is the goal me thinks .

 

[nielsc]

The way i see it is power is produced by efficiency so overfueling will sap power , so if you increase boost alone she will run lean and be down on power . So if you then nudge up the fuel screw in small increments - go for a drive power increase should be noticeable .

I did this on my 90 many times until i felt no improvement so turned the last nudge up down again , drove for a week to get used to things then nudged it up a little again and the improvement while slight was noted and so i accepted it was running at the most "efficient" burn i could hope for without fancy test equipment and left it at that .

A clean burn to avoid excessive heat is the goal me thinks .

Not necissarely, more diesel (more smoke) = more power but also more heat indeed, look at tractor pulling. But your method of tuning the pump is indeed a good guideline if you don’t have an EGT gauge. I always intend to keep smoke at a vert minimum on full load.

 

[Shayne]

Those tractors are usually running more than one turbo and boost is maxed out to win it or bin it self destruct numbers .

Fuel can't burn without air .

 

[Towpack]

Over fuelling doesn’t sap power but it does produce more heat. Watch the racing trucks in action belching black smoke as evidence of the huge amounts of power and torque they’re producing but most have water injection to keep EGTs down. You can’t tune a diesel with any degree of accuracy without EGT and boost gauges ‘cos you need to know what’s happening throughout the entire rev range and under all load conditions. JMO

 

[Road runner]

Great reading on diesel pump and performance. Will share what I can - only a weekend spanner monkey so take from it what you will.... Just sold a 91 cruiser which I had added a HPD aftermarket turbo and intercooler. I dont see HPD selling the same turbo anymore. Not sure why. Anyway the cruiser went a bit better with the mods especially on open road with revs happiest at 1800 to 2200. Down low was sluggish before and after add ons. I asked everywhere and got a dfferent story everywhere I went. The comments were I needed to upgrade the fuel pump, or spend 1500 to refurbish the pump, change timing etc etc but mostly the replies were vague and nobody knew the specifics of what to adjust and why or basically tried to apply a carpet bombing approach and piss my money down the drain. So to the internet I went and the best info I found was after searching "adjusting diesel pump 80 series landcruiser" BrendonV has a few vids which are priceless so jump on there and just follow his lead. There is also a really good breakdown of the pump and its workings on this website - so my comments are only about the noticeable differences and how to recognise them.

1 The pump has more adjustments than I understand but easy one is the off boost adjustment which is detailed by Brendon V and on this site. If this is not set right then your cruiser will barely move off park and once it does it will limp forward until it picks up in revs. Once it is set right the engine will pick up revs much easier (off idle) and pull from lower revs like you would expect a 4200 diesel to do. The diffence is noticeable in a few meters so not something that takes forever to adjust and review, adjust review.
2 The anerode is the next easy adjust (do file the angle and smooth it off so you can get it back in) WHen you pull it out you will see the different shapes to the pin and then you can install back into the pump to max setting which again improved the engine response. The basic start point is to remove it, file the angle and clean it up, and then reinstall and turn 180 degrees. Try that. From memory that put the pin around to its most "agressive" setting. - check the Brendon vid. Its much better than my short sentence.
3 There is one more pump adjust which is the preload for the boost but I was too lazy to follow BrendonV's set up for vaccum measure and the cruiser seemed to go pretty well so stopped once I had 1 and 2 sorted as best as I could tell. But pretty sure it needed adjusting becasue the aftermarket turbo was set at slightly higher boost than standard toyo one.
4 The throttle kick down cable was the silver bullet that really glued the pump adjustments together and made a massive difference to how the cruiser drove. The only proviso is that my 91 had hydraulic sensors not electronic (remember Im not a mechanic) so the cable adjustment was critical. (not sure about electronic adjust of any) I got some clues from Kaspa Transmission on North Shore who basically said drive it and adjust until you are happy with how the trans behaves. The key is to understand the shorter you make the cable the more line pressure is on the trans and this changes gear response/change in relation to load and revs. eg ...tighten up too much and the gear shifts are clunky/harsh. Get it just right and gears are held for a good range before upshifting. Have the cable too loose and the changes occur too quick resulting in not keeping the engine in power range or possibly even slippage. So adjusting just right in tandem with squeezing the most out of the pump will give you hours of fun searching for primo driving and good fuel consumption/power delivery.
5 The measure for me was simple - the cruiser was relatively peppy off the mark, gobbled up long hills like Brunderwyns and didnt downshift all day. It may sound like bull but the cruiser went form needing shift down almost every hill to not needing to shift down unless slowed by traffic. I cruised at around 95 to 105 which was around 2000 revs. RIght where the power was for the truck. When I had it bang on the truck surged noticebly forward when it changed from drive to o drive.

On long trips I got around 620 to 650 if running down to reserve and around town mixed with motorway around 500 to 550.(never below 500 unless towing) I reckon there was more to get like better throttle response down low and get rid of an annoying flat spot at 1750 rpm which was definitely less noticeable after air filter change. NOTE - truck did have intercooler which I swapped off onto another truck that Ive bought (93) but the small flat spot still there. ...so not due to extra lag from intercooler installation. Truck has a 3 inch exhaust which would help with mileage and heat reduction and probably a little more power too.
Going from muds down to more road biased tyres took revs up to 2200 at 100kms - geared it down a little but on these old girls a little adjust makes a big difference on how they perform. Im going to invest some cash into the next one and if any ones inetersted then let meknow and I will post some detail/pics of upgrades and general chores to be done.

 

[Road runner]

Oh and short note on overfuelling = overheating - again all sorts of opinions but the best I can say on that is;
1 Install temp gauage if you can (im going to at some stage becasue I tow and I live up north)
2 Ive read that pulling load in higher gear will heat up much more than dropping down a gear - makes sense really
3 Nice big exhaust to get hot gasses away asap - do it. WIll go faster too
4 I installed intercooler to help with heat and aux trans cooler. I noticed a real difference in temp build up around the transmission well (beside my left leg) after I installed aux trans cooler so probably will install another.
5 My most mechanical (qualified) friends say dont overfuel - you will cook your engine. I would go with that for sure!

 

[frank rabbets]

Interesting post RR. Do you have a direct link? I can't find it for the life of me.

 

[Shayne]

Is this what you seek Frank