Cylinder #2 down on compression. SOLVED.

[Aust162]

This is a bit of a saga and i know i've made a lot of mistakes but i have been trying to save money and keep costs low on my daily toy car.. Ohh well, sh*t happens and less money for the panelvan now

I need help with this Starlet GT engine I've been playing with. Its a 4EFTE (turbo DOHC 16v 1300cc) I brought it cheap (basically condition unknown) and dropped it in my EP91.

I compression tested it before fitting it. got 160, 60, 30, 160 psi readings! i put oil down the spark plug holes and the compression jumped up to 150 in 2&3 cyl. i thought maybe the rings were stuck because the motor had been sitting in a backyard for at least 2 years. i then decided to fit and at least get the wiring sorted.

Turns out the engine ran fairly well, slight miss on idle and hesitant on start-up..But it boosted well and was pretty quick!

A week later it started using coolant, water temp gauge would spike for 10-20 secs then drop back to normal. i suspected H/Gasket.my boost/vacc gauge showed an unsettled vacc reading.

looked down the spark plug hole on cyl #3 and could see the piston top was "steam cleaned" (thats where the coolant was going). overflow bottle was also pressurizing.radiator was bubbling.

I then pulled the head off , found a break in the gasket on cyl #3 blowing into the water gallery. I cleaned the two surfaces thoroughly, fitted a new toyota h/gasket with a light coating of hylomar spray, new headbolts torqued to spec.

It ran okish but not perfect. it was difficult to start in the mornings or if you let it sit for a few hours.i drove it for 3-4weeks not really beating on it out of fear it would stuff up! . i then decided i needed to "test" it, so i took it up the hills one night, flogged it (turbo glowing). on the way home the car is missing badly on idle, feeling very sluggish off boost. engine is "put put putting" out the exhaust pipe. engine oil has blown everywhere out the pcv hose and out the top of cyl 2# spark plug tube seal (on valve cover gasket)

I then comp test the motor again and get 170,55,165,165... not surprised at this point. (cyl #2 is now down, not cyl #3 though)

Next i pull the head off, get it machined and serviced (valves seal well, no cracks, slight warp which is fixed). Head re-conditioner suggests i not use hylomar spray and he thinks that was basically the issue. the hylomar spray!

Today i refitted the head with a new Toyota h/g and new headbolts again. starts up fine and idles near perfect. go for a light drive (revs below 3000rpm and max 6psi boost) drive it for 15 mins and start getting uneven idle, vacc gauge "hunting", "put put" out the exhaust. After 15mins of driving, oil has pushed past the spark plug tube seal on cyl #2 and out the pcv, oil everywhere all over the valve cover the inlet mani.. the usual story for me with this engine!

I comp test it straight away after this. i do it a few times and get 50-65psi on cyl 2#. all others are 160-170psi.

As i said before, i know i've made quite a few errors/short cuts trying to repair this engine. luckily it only takes a couple hours to pull it down, but i am getting a bit tired of it at this point

Anyone have any suggestions besides using the motor as garden ornament, boat anchor, 90kg paper weight?

though on a serious note, i think its now a bottom end issue. cracked ringland?

p.s i have pics i can upload of the bores, head, block etc if thats a help.

Any help appreciated,

thanks guys

[Omegaman]

Hi im no expert, but what does yr spark plugs say?
Number 2, all oily or other. Check all to see the differences.
Sounds like rings to me.
Could you undo engine mounts, raise engine slightly and take off sump.
May allow u to undo no.2 rod and pull out piston for checking. Head needs to come off, again.

[stidnam]

Did you check the block to make sure that it is flat when you got the head done? A warped deck could be your problem

[MRMOPARMAN]

get an air fitting that fits your spark plug thread, and a pressure regulator. put no 2 cylinder on compression cycle TDC, connect the pressure reg to your air compressor, and the fitting to number 2 cylinder.

air up the cylinder (don't use too much pressure or it will spin the engine over) then:

stick your ear up to your exhaust tip. if you can hear the air rushing out the exhaust, you know you have a problem with your exhaust side (valve/seat/cam etc)
stick your ear in the airbox. if you hear air rushing out, then you have a problem with your intake side (valve/seat/cam etc)
undo the oil cap and stick your ear there. that would signify problem with piston/rings/bore
take the plugs out of no1 and 3 and stick your ear there (you might need to use a piece of hose to hear it correctly), that would signify head or h/gasket problems (unlikely, comp would be down on 1 or 3 if that was the case)

or buy a leak down tester (above is just a poor mans version, you cant measure the amount of leakage above)

[Aust162]

Thanks guys, plug looked just like the others. It wasn't fully or oily. It's quite strange. Ill take some pics of the plugs anyway.

Deck I did not check for flatness. It could well be the problem, but when I took the last gasket off there were no marks (carbon/soot) on the gasket. It's a cast iron block too so I was thinking it wouldn't be very likely. Though 7ms warp all the time!

Omegaman, the sump will just drop easily, (no crossmembers on this) car, but I was under the impression I couldn't pull the piston and rod out the bottom unless I remove the crankshaft..? I know I can unbolt the big end rod.

[MRMOPARMAN]

if you got the head machined, the head shop will have machined the deck as a matter of course.

don't lift the head off just yet, there will be tell tale signs if its bhg or cracked head.

[Omegaman]

Omegaman, the sump will just drop easily, (no crossmembers on this) car, but I was under the impression I couldn't pull the piston and rod out the bottom unless I remove the crankshaft..? I know I can unbolt the big end rod.

As a last resort after all the checks mentioned. i meant to take the sump off, undo the rod bolt, take the head off and put the piston out of the top.
The idea was just so u dont take out the whole engine.

If the head was warped, u would think that low compression will be on more than one cylinder.

also just check these youtube sights.

http://www.youtube.com/watch?v=WgrfT0LFMhc leakdown test and

http://www.youtube.com/watch?v=X_tbksFYhl4 compression test

[ta22fan]

Usually a large difference between dry and wet compression test means rings.

[Aust162]

Mrmoparman - thanks heaps for your post, i was hoping there was a DIY test just like that that i would be able to try i have all the gear to rig that up so i'll definitely be giving that a crack tomorrow if i get the time.

Omega - that makes sense. i wish i could just pull the sump of (leave the crank in place) run a hone up the bores and put new rings on it! (if it indeed ends up being rings at fault)
I'll check those links too. thank you

ta22fan - that is what i've been reading. when i first got the engine i had 60psi in no:2 and only 30 in no.3. after giving it a good squirt of motor oil the compression jumped right up to 150-180psi IIRC.

I will update this thread with my findings hopefully soon.

[Aust162]

just read over the invoice for the cylinder head:

*chemical clean cyl head
*vacuum test head and bend check
*mill head surface
*enviro, consum & energy levy

I asked him if the head would have been causing my issues described. (i basically explained the whole story to him too) He said " the head was not badd.. had a slight bend in it but nothing major." " i think you will find the whole problem was the hylomar spray, dont use that this time"

He also said: "I dont have the blocking adapter plates..? to pressure test the head, but the vacc test was good so i wouldn't have really needed to do that anyway. i'd only be over servicing it if i did"

[MRMOPARMAN]

ill admit im far from yoda when it comes to motors and shit, but ive hylomar'd quite a few engines over the years, and never had an issue. I use it religiously.

and if the head was rooted, you could be losing pressure into other cylinders (or vice versa), or water in oil (or vice versa) or combustion gas's into radiator etc etc.. there would be other tell tales.

aren't you pure insanity's cousin or something? tell phil to get off his arse and help you out

[allencr]

You don't need to listen to the in&ex ports for leaks if you already know that the wet test really bumped up the compression. You only listen if the oil didn't get it near normal, and even then you'll already know that it has to come apart.
CHECK the block!!!
QUIT getting new bolts!!!
RE-TORQUE the head!!!
Threads in block clean, washers smooth, threads & washers oiled?
Prevent Head Gasket Failures

[Aust162]

ill admit im far from yoda when it comes to motors and shit, but ive hylomar'd quite a few engines over the years, and never had an issue. I use it religiously.

and if the head was rooted, you could be losing pressure into other cylinders (or vice versa), or water in oil (or vice versa) or combustion gas's into radiator etc etc.. there would be other tell tales.

aren't you pure insanity's cousin or something? tell phil to get off his arse and help you out

I was under the impression hylomar was pretty awesome as well..

I was getting combustion gases in the coolant initially. that has seemed to stop. oil has always stayed clean.

Haha yeah Phil is a mate (not a relative). he's never playing with cars these days, seems to have outgrown it im still waiting for the day when i do

[Aust162]

You don't need to listen to the in&ex ports for leaks if you already know that the wet test really bumped up the compression. You only listen if the oil didn't get it near normal, and even then you'll already know that it has to come apart.
CHECK the block!!!
QUIT getting new bolts!!!
RE-TORQUE the head!!!
Threads in block clean, washers smooth, threads & washers oiled?
Prevent Head Gasket Failures

check the block means engine out and off the the machine shop i guess
Headbolts are torque to yield, so i thought im doing the right thing by buying new ones..?
Head is torqued as per workshop manuals, head bolt instructions. 20nm,40nm, 90degrees on 3rd pass. im using a "warren and brown" torque wrench (not a cheapy)

cleaned the threads super well, washers def smooth and oiled under the washers and bolt threads each time.

[StuC]

Andy,
i'd be looking at rings with a high chance of broken ring land. If it has been previously boosted/thrashed near 180whp you're pushing bottom end.
I have my grey one for sale if you want it..............