Overheated Lancer

E

enigmas

Member
Hi guys...just a quick recap from my introduction to the forum. My query stems from an problem I have with a 1998 1.5 litre Mitsibishi Lancer coupe that was gifted to one of my daughters. The car was totally reliable for the 16 years my wife and I used it, only letting us down on one brief occasion when a dodgy key failed to work with the engine immobilizer.

To cut to the chase, my daughter acquired the car (quite recently) and unfortunately the radiator top tank seal started weeping, which then led to an eventual over heating problem...big time! During a run along a freeway the engine purged most of it's coolant and then cutout. No, she didn't notice the temperature gauge virtually off the scale until it was too late! The spark plug boots virtually melted. Having said that....my task is to now repair the car! Fortunately the engine and the car was well cared for before the incident. The engine didn't seize but the head gasket is blown. So the cyl head has to come off regardless and will be refaced. Water did enter the cyls and pressurize the radiator. That also requires replacement.
Before I undertake the head removal, repair, etc, etc, I thought I'd start the engine and run it for a minute or so (obviously no coolant in the block) and listen for untoward noises and any other signs of distress.
Interestingly (and more annoyingly) there's a seemingly unrelated issue. When I crank the engine there's spark to the plugs but the fuel pump is silent. If I 'jump' 12 volts directly to the pump from the battery the pump runs. If I crank the engine there's a pulse to the injectors (verified on my multimeter), but it won't fire.
So what's stopping the pump from running...the engine immobilizer(?)...this was working fine prior to the over heating episode! Or could it be another sensor failure, perhaps the coolant temp sensor?
I'm not aware of any inertia switches fitted to these cars?

Any clarification on this issue is most welcomed.
 
An engine that has been overheated so badly will most likely need new rings and may have hurt the pistons. In the extreme overheat the rings will have relaxed so if not replaced the engine will burn lots of oil.
 
Hi Frosty...thanks for your reply but you've not answered my query! The mechanical aspect is straight forward...not of concern at this time. When I get it started I'll address the related mechanical concerns.

This is what I'm asking.
"When I crank the engine there's spark to the plugs but the fuel pump is silent. If I 'jump' 12 volts directly to the pump from the battery, the pump runs. If I crank the engine there's a pulse to the injectors (verified on my multimeter), but it won't fire.
So what's stopping the pump from running...the engine immobilizer(?)...this was working fine prior to the over heating episode! Or could it be another sensor failure, perhaps the coolant temp sensor...but I can't see how that would stop it from firing? I'm not aware of any inertia switches fitted to these cars?"

PS. Both the Engine Control Relay and the Fuel Pump Relay both function when removed and bench tested. Obviously though the FPR is not activating when the ignition is switched on!

Does the FPR have a fuse...and if so, where is it located?
 
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when you jump the battery directly to the pump, whereabouts are you attaching each end?

i’m thinking, maybe there’s a burned out fuse or relay in between there that your jump is bypassing?

have you tested for continuity of the pump’s power cable? maybe its insulation has melted off somewhere and it’s shorting to ground instead of running the pump
 
I jumped 12v to the black/blue wire (under the rear seat driver's side) to the fuel pump connecter directly from the battery.

Yes, I suppose I can trace the Blk/blue wire back to the FPR or test if the relay is feeding power out to the pump with the ignition on.

Where would this fuse be situated?

One other question. How do you know if the immobilizer is functioning...if the key is turned to the start position but the engine is not cranked over?
 
i’ve just had a look at a wiring diagram (in the gregorys book) and i don’t think there’s a fuse on the fuel pump line (other than the one the whole ignition switch hides behind) so i guess there isn’t one? idk, i’d have a stickybeak in the fuse boxes and see if something is labelled, but you sound like you know what you’re doing so i guess if there was one there you’d have found it already

no idea about what it looks like when the immobiliser kicks in, hopefully someone else can chime in. i’ve had an immobiliser issue in a different car a while ago but for the life of me can’t remember if it would crank but not fire, or not even crank. i would speculate, though, that if it was immobilised it wouldn’t pulse the injectors? which might suggest it’s not the immobiliser stopping it from starting

oh, if you have a spare key, does it behave any differently with that?

hmm thinking more, my mazda has a blinking dash light for the immobiliser which turns off a few moments after turning key, it looks like a little key icon. if it doesn’t recognise the key, the light keeps blinking. does the lancer have similar? i can’t remember (and i’m in bed lol)
 
Thanks pelican, a bit of to and fro on the issues helps to clarify the possible causes. I've driven this car many times over the years (wife's car) but never really paid much attention to the dash lights. I sure there's a programmed routine (as you've mentioned) with an engine light that stays on for a period or whatever when the key activates ignition, but I can't recall it. Perhaps someone who specifically knows could chime in?
I'd like to discount the immobilizer completely...then it would just be faulty wiring/component somewhere in the fuel pump circuit.

PS. There is another key...but my daughter is currently away so I'll have to wait a few days to try it.
 
I've moved on with the mechanical side of repairs to the Lancer. The head is now off and the condition to the cyls, pistons, head and valves can be assessed. My next task is to remove the sump, remove the big end caps and push the pistons out...then check out the piston thrust faces and ring lands. Considering the epic overheating situation...the internals stood up very well!
Here are some pix of the engine in a partially dismantled state in situ.

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Fuel Pump Operation.
As far as I can currently discern, the fuel pump only functions when the engine is cranking over (obviously) on the starter motor and/or when the engine fires and is rotating of it's own accord, i.e., when the ECU picks up ignition signals from a running engine.
 
Here's some follow up information that may be of use to those in a similar situation regarding the condition of the Cyls, Pistons, Rods & Big End bearings:

Cyls.
Fortunately there was no scoring. The cyls were glazed slightly with no blued sections/spots or any discernable lip. This engine has done 365,000 kms reliably until the overheating episode. The glazing IMHO would be normal for a car that has covered so many kilometres. I gave the cyls a deglaze using a hone with 240 grit stones.

Pistons.
The top compression ring was jambed tight on the thrust sides of the pistons in several spots (generally 2) on all but number 1 piston. The very top edge of the piston above the land had just nipped the cyl walls on cyls 2, 3, and 4. The reason the engine compression read so low was that it was blowing past the 'jambed' section of piston ring and the skirt. Once removed the rings still illustrated useful tension. I carefully removed the top rings on each piston and checked the ring lands which were amazingly still well within tolerance for side clearance.

The 2nd ring is slightly thicker...these illustrated no damage at all as did the ring lands

The 3rd composite ring (oil control/scrapper) was flush faced with the piston skirt...so wasn't doing anything other than filling the ring land space. My view is that it had been like this for ages and was stuck in place by virtue of the carbon carried in suspension by the engine oil.

This engine only used oil during short trips, stop start driving. On long trips...2 this year to Coolum, Queensland from Victoria it used no oil at all!

Piston skirts.
No scuffing literally no damage at all.

Big End Bearings.
The bearing inserts all checked out fine with negligible wear...likewise the bigend journals are in amazingly good condition. The car has had regular oil and filter changes, generally 2 a year during it's life.

I'm getting a new std ring set from Repco ($55). Interestingly the oil control ring on this engine can be 2 sizes...either 2.8mm or 3mm. Mine are the former. So always check before purchasing. The compression ring and 2nd ring are the same but of different widths for all 1.5 engines.

I'll post photos of the rods and pistons when their ready for refitting.
 
A section of this post is derived from here... http://www.auslancer.com/index.php?threads/tighening-head-bolts.5064/ of which I've added FYI an entry below.

The cyl head is currently being surfaced by a mate (Basil) at Headworks Murrumbeena.
Reading the torque sequences (WSM and link above) is kind of interesting and in some ways archaic, if not confusing and on par with the cyl head tightening sequences of my 1942 WLA air cooled motor cycle (military workshop manual) where it's all done by 'feel' literally in the field...and I do mean field!

NOTE:
Below in italics is the head torque tightening sequence taken from Ron's initial post.
The initial torque figure given in Nm for a 4G15 engine (1.5 litre) is 49Nm or 36 ft lb, if using Imperial torque loading specs.

I've got a Warren & Brown torque wrench bought in my youth that I'll be using for the task and to also find out what torque the 2 extra 90° wrench turns apply.

I note that the bolts are specified torque to yield (i.e., simply put...a stretch bolt) The head bolts are being replaced with new as the engine had a severe over heat cycle (daughters will do that!) but I'll be reusing the conrod bolts as that end faired well.

As far as the conrod bolts go though...I'll use the WSM two stage method once on one rod to gain an accurate torque reading...back off and retorque to that figure. I'll then simply re-torque the other conrod bolts to that figure.

As part of the process though, I'll fit one complete rod with piston but minus the rings, then turn the crankshaft over several times to see if any bind is evident. Over torquing rod bolts is a bigger issue which can readily lead to seizure on a journal.

I'll be looking for a torque loading somewhere in the 30 - 35 lb ft range (41 - 48 Nm) which is pretty standard for a conrod torque across a broad range of engines (V8, 4 & 6 cyl) using similar conrod design.

All the threads/will be oiled (using engine oil) before torquing. Although torque to yield bolts, I'll use loctite threadlocker 272 as added insurance on the conrod nuts.

4G15 (1.5 litre)
Cylinder head bolts 49Nm initially (in sequence)
* It seems...unless I've missed something...that the initial torque sequence is done in one go. This is generally not good practice and I'll do it on 2 stages to minimize distortion on a freshly surfaced alloy head.

(From Ron's initial post below...I've changed the Nm number to 49 to suit the 1.5 litre 4G15 engine)

Cylinder Head Bolts.

Step1: 49Nm (in sequence)

Step2: Loosen fully in reverse order

Step3: 20Nm (in sequence)

Step4: Turn 90 degrees additional (in sequence)

Step5: Turn 90 degrees additional (in sequence)

The book describes refitting the head by noting the following:

1. Tighten the bolts in several stages following the proper sequence to the specified torque.

2. Assemble the engine, start the engine and run to normal operating temperature.

3. Shut off the engine and re-torque the head bolts, unless the gasket manufacturers states otherwise.

With the 4G13 engine you worked the bolts up to 73Nm and with the 4G15 you worked the bolts up to 49Nm, warmed up the engine, and with the torque wrench still set to the torque figure for that engine you go over the bolts again. That’s straightforward. The bolts might turn. They might not.
 
Latest update regarding the conrod bolt torque settings. I just applied the WSM method and then checked the loading on the rod nuts with my Warren and Brown tension wrench. The figure I arrived at was 25 ft lbs of torque on clean, dry threads (12mm conrod nuts).

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Here's a few photos of today's effort. The pistons, rods, oil pickup, sump and sump to transmission brace are all back in place. The engine crankcase is effectively buttoned up again.

NB.
Note the second image where I'm poking a scriber into one of the oil scraper return holes. Virtually all these holes on each piston in the 3rd ring land were blocked/clogged with carbon. I cleared them using a small bit in a cordless drill.

The ends of the oil control ring's expander segment were marked with a paint pen (red & yellow) to assist with correct assembly.

The engine turned over easily with the pistons and rods in place...no binding. Assembly lube was used for the bearings and journals.
Copious engine oil was used when fitting the pistons to the cylinders.

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I just picked up the cylinder head from my mate Basil this morning. What an amazing transformation. It's been cleaned, faced, valves cut and lapped including the seats. New stem seals. None of the valves were seating correctly due to the severe overheating and lapping alone wouldn't have restored them. The camshaft journals were also lightly linished. Here are some pix!
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Basil (of Headworks) assembling the cyl head.
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The completed cyl head
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Fitted the cyl head, inlet and exhaust manifolds, the injector rail and reconnected most of the sensor plugs today. I picked up a new radiator and thermostat as well...this will be fitted next visit to the car.

Torquing the head bolts...now that's a stressor. I checked all the bolts for size per WSM with my digital verniers and they well within specification. I followed the 5 stage torque process, then on 2 centre bolts checked the torque loading which came to 50 ft lb (68 Nm). I wouldn't be game to apply any more torque to the bolts as they felt as though they might shear at anything greater than this loading.
The WSM doesn't state whether the technique for torquing the bolts is to be done dry or with a lubricant applied to the threads (usually engine oil) and the head section of the bolt to reduce friction. Bolts will torque quite differently when dry and when oiled. This would also affect the bolts yield loading if the WSM method is adhered to. I'd rather use a specific torque loading using a quality wrench than just arbitrarily pulling a bolt head through 90° twice!

PS. Do bolt the inlet manifold to the cyl head before fitting it to the engine block. Otherwise fitting the retaining bolts on the rear the manifold could be something of a contortionists nightmare!

As an aside, it's interesting how the large coolant pipe behind the head seals to the thermostat housing with just the interference fit of an O ring.
 
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Nice write-up and good job on the head, only just read the post. I see you have almost exact same torque wrenches that i have, mines a 70's warren and brown with the floating end handle, other is warren and brown pointer needle model 3420, except this one has the large round Bakelite looking plastic knob on the end , good old school gear, i think from what i can remember (which is fading slowly) i bought mine back in the 70's.

I always use the same method as you are doing, forget the 90° twice method, as you said good quality torque wrenches set to correct torque, oh and i always oil bolts as well with engine oil, never dry, these new workshop manuals are at best a bit vague in certain areas.

I know what you mean about the o ring with the coolant pipe, when i fitted mine back on i thought for sure this is going to leak like boys at a bucks night, think i just used thin wipe of rubber grease on o ring as well, 4 years and 20,000 klm later as dry as a bone, when i fitted new radiator (not aluminium) i just used distilled water/concentrated coolant, all seems good so far. I don't know what thermostat you have, but mine was a 2 stage one, luckily caught it just in time as it was starting to seize/bind on side wall.
As far as water pumps went i had choice of using $60 trade price gates or $230 orig Mitsubishi water pump, i bit the bullet and wallet and went the dearer option, figured that orig one was still going strong after 14 years, hopefully this one will be just as good, only reason i changed it i was in there anyway so it was prob bad call if it didn't do w/pump/tensioners/belt/ complete set hoses as well, even though it was still too early for belt change.

Anyway good luck with the remainder, keep us posted.
 
The little car is back together with only a few unrelated electrical gremlins to sort. It started virtually instantly (would have been more instantly had I remembered to reconnect the distributor plug which I'd disconnected whilst priming the oiling system)

See link below for electrical issues.
http://www.auslancer.com/index.php?threads/electrical-conundrum.10265/#post-234220

Here's a very brief video from my phone of the engine running. A bit tappety...but I'll let things bed in for a while before readjusting them. The exhaust is clean running, it holds its coolant and the only smoke to be seen was oil contamination burning off the engine surfaces for the first half hour.
 
One last question guys. Is there a requirement to retorque the cyl head bolts after a given time? There was no reference to this in my Gregory's WSM.
 
Normally , best practice yes you do, typically around 1000 Klms later should be a safe bet.
 
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