Major Problems - daihatsu HiJet 1.2 diesel



Hope someone can help with this problem.

Purchased the vehicle a few months ago to start a catering business (Vehicle already modified). Finally got the business started this week on Monday.

After driving for about 2 hours (lots of stops), suddenly and most noticibly on bumpy roads the vehicle revs itself. If I'm in gear the causes acceleration, so I naturally take it out of gear which causes a max rev for about 5 seconds, then back to normal. During this a massive amount of black smoke comes from the exhaust. Again about 20 mins later same again. I take it out of gear and again massive rev noise from the engine and more smoke. If I keep accelerating rather than taking it out of gear I still get a lot of black smoke, but not the revs.

To make matters worse I was pulled by the police yesterday for the exessive smoke. He followed my for 4 miles and said he only noticed it once, so the smoke is not permanent, just on those occasions mentioned above.

I'm obviously panicking as I've purchased this vehicle and paid more as it's modified by Jiffy for catering. Hard to get hold of.

I've checked the acceleration cable is not sticking.
I've checked the oil and must have lost a good 1/2 pint from one mornings work of about 50 miles.

My father in-law is convinced the engine is 'knackered' and the vehicel needs scrapping. Not that easy when you need it daily for work, so I'll probably cling to any possibilites which could cause this.


First the good news. It ma

First the good news.

It may well be something simple like the injector pump sticking/seizing, and the oil consumption may well just be knackered oil. First up, find a local diesel specialist (Not the Daihatsu dealer!) and take it along for a good engine service/setup. DONT attempt it yourself!

Now the bad.

Lots of desperate owners come onto this site regarding this van in it's diesel guise, and the facts are fairly blunt - this lump is not known for it's longevity, and most owners have taken the hit and sold it on, or converted to the petrol unit. You wont be the first, or the last!
This particular engine is made by a company called Lombardini, an Italian company who specialise in slow revving plant/industrial engine applications and this hi revving, complex unit is made especially for Daihatsu - and they didn't do it for long. Consequently, knowledge and spares are very thin on the ground (All these Hi-Jets are in fact made in Italy by Piaggio, the scooter people, and just rebadged as Daihatsu)
IF the worst come to the worst, your best scenario would be to source a reasonable (petrol)chassis and bolt the specialist body over - or, with a little more work, convert to a petrol engine.
I'm wondering if a Suzuki supercarry/Bedford Rascal would be a suitable chassis.

Dave with a Sporty

Dave with a Sporty

HiJet Diesel Engine Problems

Getting back to basics the engine is a heat engine and its main enemy is heat. In particular the alloy head will expand about 1.7 times as fast as the iron block. When worked hard it will get hot and gasket failure before 25,000 miles seems fairly common on diesel Hijets. I heard through the grapevine that a marine diesel expert (marine versions of the Lombardini LDW 1204 also exist) based in Plymouth really detests these engines however all is not lost. Engines that are overworked and fail prematurely can be rehabilitated with uprated gaskets. The latest technology is MLS gaskets (Multi Layer Steel) With these gaskets there are several layers of cigarette paper thin stainless steel sheet each coated with Viton (chemically resistant rubber that is OK up to 250 deg centigrade) Possibly with such a gasket and an oil cooler the engine will be OK, however some Lombardini agents may still have the old pattern gasket in stock so beware. Allegedly MLS gaskets and steel dowels will even rehabilitate the notorious "pretend 4x4" that was designed for the school run but got used for towing double horseboxes (curiously the same engine was perfectly OK in a sports car). Possibly the 4x4 design was at fault as one can virtually guarantee that all car engine designs are dyno tested for hundreds of hours at the factory. The major difference of course is that the factory dynamometer test cell will have an invincible cooling system whilst in general the car will not. Heavy loads or overloading of the vehicle will also result in low road speed hence low airspeed so the cooling becomes ineffective. Cest la vie!

Re Dave with a Sporty. Look

Re Dave with a Sporty. Look on the Internet for "Kei Cars" or "Kei Trucks". Allegedly the Japanese government taxes vehicles on length, width and height (not sure about height!) as well as cubic capacity. The result is that a lot of vehicles are about the same size. The Kei class allegedly also qualifies for a lower cost Japanese MOT. The downside is that Kei vehicles are not really suitable for autobahn type motoring although the latest designs do get over 50BHP from the Kei class maximum cubic capacity of 660cc. Fuel injection and 4 valves per cylinder are used with a redline at 7000 rpm! As to demountable caravan bodies many vehicle swaps are possible although there are no really powerful Kei sized trucks as far as I am aware. Possibly the old VW Caddy pickup would adapt if the side panels are not load-bearing. Good Luck.

Hijet Diesel 1.2 pumps timing

I had the job of pulling my mate's hijet Diesel, (headgasket) anyway taking the top apart and putting them down in sequence my mate came along chucked them in a box(doh)got it all back together run like a bag of s**t, so what I done was turned engine over so the lobe was opposite the injector roller, undone lock nut, wound out then wound in until just kissed on all of them, it ran just with smoke everywhere, screwed them all in one turn, ran better so trial and error, was 2 and a quarter turns and runs like a dream, and has been for a few months.The only pain was on and off with the rockerbox cover, if you don't screw it down good oil pumps out like a good'un, not thrown out by the camlobes but a oilway, just remember the lightest of kiss to touch down, and 2qrt turns.

Re: Major Problems - daihatsu HiJet 1.2 diesel engine

This engine has a wierd set up and should only be worked on with reference to a workshop manual, which I can supply. The high revs could be the engine is gummed up especially around the speed governor, usually caused by infrequent oil changes. You could try running some flushing oil first. The injector timing is set by a complicated method on these things and should be left well alone as it can only be checked by a specialist with the equipment to do this. If you have no joy finding anyone local then contact me and I'll discuss further with you.

PS Sorry for the late reply, not been on the site for a while.

Major Probs with Hi-Jet Diesel Engine

I know this is an old thread, but I thought I'd let you know what the problem is.

As Johnny Sprinter states, this engine has a weird set up especially with regards to the injection system. The acceleration is controlled by a system of cables/pulleys/rods adjusting the fuel setting on each individual injector - inside the rocker cover. The point where the control mechanism enters the engine is through a casting on the front end of the inlet manifold. The problem you have with revving and black smoke is caused by a failure of the inlet manifold gasket (possibly the bolts vibrated lose and just need tightening) thus letting oil from the engine into the inlet manifold.

Only a small amount of oil is required in the manifold which will creep up with the air flow and enter the bores causing the unexpected accelleration and smoke. This will be accompanied by a louder than usual knocking sound which sounds at first as if the big ends have given up. Unfortunately as the engine is at this point running on engine oil on at least one cylinder it cannot be switched off via the key and should be stalled as soon as possible to prevent over revving and upsetting the locals with a huge cloud of blue/black smoke.

The remedy is if you are lucky as quick tighten up of the bolts especially at the forward end of the manifold, if this fails then you will need to have a new gasket fitted. This is relatively easy but there are a couple of bolts that are arkward to remove and there is also the connection of the throttle linkage inside the housing. I wouldn't recommend a home fix unless you are competent with a box of spanners. Incidently, the gasket costs £28.05 (a huge price for a piece of paper, but a cheap fix really) and takes up to a couple of hours to fit.

This is a common problem with these engines and gets quicker to sort with practice!