Bluetop blowing smoke with no power

[mike227]

Hey guys, sorry I wish this didn't have to be my first post but such is life.

my car:

1986FX-Gt in red
1986 Blue top with tvis,
Only modification a pod filter (it came like that, havent had it long!) and an after market muffler.
Its done 193000k's

For the last couple of days occasionally the rev's have been idling at about 1k then reving up to 1.5K then dropping back down, this goes away after a few mins.

Then last night heading into town it lost most of its power and blew massive massive ammounts of smoke out the exhaust (and small hole in the front of the exhaust)

Pulled over straight away, the 2 things we could identify (in the dark and rain with our cell phones), was that a pair of hoses that appear to lead to a sensor of some kind, off the intake end of the tvis, the closer one to the front of the car had come off. And It was very very low on water in the raditator (this has never happened before, but I hadn't checked the radiator in a week)

There is plenty of oil (possibly too much but I dont think so, right at the top of the cross hatching on the dipstick). After letting it cool a little, and reattaching the hose (will work out what is it when I get it back into the garage and hit the manual) it went a little better, but we parked it up and walked into town.

Were about to head back and tow it back to my house (stayed at a mates so dont have access too the workshop manual), but thought I should put a post up on here before I go incase anyone knows anything that may help(or wants to sell me a black top 4agze cheep as chips ).

[rollaholic]

your rev issue will probably be caused by the idle speed control valve, pretty common problem on 4ages - as seen on the bottom of the throttle body



you can replace it or throw it away and blank off the ports with a plate.

as for the smoke... did you notice the color? and had you been doing anything (skids) beforehand?

low coolant not a good thing!

[mike227]

Sweet I shall get onto that throttle and see if thats the issue (the engine bay is such a mess I didnt know where to start.

I dont do skids, but I do drive it fast-ish (but safe and legal), but I dont thrash it.

After heading back and towing it home today, I think the smoke is actually steam , and I'm pretty sure I've blown a head gasket, when idling with the radiator cap off (cold engine!!) water shoots all over the place and then topping it back up a whole lot of white smoke and steam (this time) came out .

Heading back down to uni tommorrow (car lives in wellington) for a few weeks and when im back I'll see where it goes from there, I believe a compression test shoudl give me a pretty good idea weather a gaskets blown.

[rollaholic]

the best way to detect a compression leak into the coolant is with a TK test, or a leak down test.

i asked about skids cos sustained high rpm can cause oil to collect in head on 4ages and make its way into inlet manifold for smoke-o-rama.

experienced that myself this weekend, just by the by.

missing coolant is a bit of a giveaway if its not leaking though!

[mike227]

Well, its buggered alright.


Havent enquired about the price of having the headgasket changed, but I can imagine it isn't cheep. I'm more a bicycle mechanic than a car mechanic, I'm pretty sure with enough time I could do it myself. For now though I'll probably just drop a redtop into it, not after huge performance or anything, but a small port red top seems to be the way to go, hopefully avoiding needing certification aswell.

[rollaholic]

smallport will be a nice upgrade, make sure you get complete engine (inlet manifold, injectors, loom, ecu etc) to get the most out of it.

[pc]

The loom for a smallport doesn't plug in... be prepared to do some electrical work.

[rollaholic]

doesnt plug in in what respect?

[pc]

The plug on the engine loom that plugs into the rest of the internal loom is different from the AE82 to the AE92.
The plugs to the engine bay fuse/relay box are also different.

[rollaholic]

eh that third plug is really just power supply for ECU, nothing a soldering iron and a couple of pinout diagrams cant fix. and teh fuse box one just needs a bit of customising

[mike227]

Back home now, I've pulled the plugs, drained the remaining coolant, and turned the engine over with the starter motor, bit of water came out of where the spark plug goes in, cylinder number 4.

The haynes manual hasnt been much help (disconnect the throttle cable to take the valve covers off??), so does the head come off the block in once peice? or must it be fully dissasembled?

At the moment ive got the bolts off the top of the valve covers (and the centre cover is off) but the valve covers just wont move, how much force shoudl I be using?

[cat007]

tap it with a hammer?

[rollaholic]

yeah give it a bit of a tap, or get a flathead screwdriver and put it in the gap the gasket creates between cover and head, give it a twist to break the seal.

try not to mark the head too much

you'll need to pull the camshafts out to get to the headbolts, but you should be able to get the head off with inlet manifold still attached.

[jondee86]

Hey... I found the problem with getting the camshaft covers off the
engine was mostly due to the little rubber seals getting baked onto
the studs like Nyloc nuts !!!! These are the seals that go underneath
the chrome nuts that hold the cam covers down.

Easiest way I found to get them loose was to work on the seals with
the smallest flat blade screwdriver I could find. Lever them up a little
at a time by getting under the seal at either side.

Once the seals are off the studs, the cam covers just lift off

Cheers... jondee86

[mike227]

Hey... I found the problem with getting the camshaft covers off the
engine was mostly due to the little rubber seals getting baked onto
the studs like Nyloc nuts !!!! These are the seals that go underneath
the chrome nuts that hold the cam covers down.

Easiest way I found to get them loose was to work on the seals with
the smallest flat blade screwdriver I could find. Lever them up a little
at a time by getting under the seal at either side.

Once the seals are off the studs, the cam covers just lift off

Cheers... jondee86

Yeah I think it was mostly them, they looked like they hadnt ever been off since the engine was new, and the rubber on them is quite hard and a bit messed up.

I think i'll go for changing the head gasket now, a redtop would be nice, but repairing the blue top probably a lot quicker.

[jondee86]

Good call. You will have more fun in the blue top for less money
and with less hassle. I changed to a small port, and while it has more
grunt than the blue top, it is taking a lot of time, effort and money
to get it to be as rev happy as the blue top is from day one.

Bang for buck, you will not beat a blue top

Cheers... jondee86

[mike227]

We have progress (my previous car mechanical experiance: radiator flush and oil top up)

Last night pulled the intake and exhuast manifold off. It went pretty well, no stripped bolts , how ever the ehaust manifold was missing a bolt! and managed to stab myself with the distrubtor heat shield between my thumb nail and thumb, not cool. all looking pretty good though, everything came off cleanly. 40 resealable sandwhich bags for $3 at the super market so all the bolts and bits and peices are nicely (and cleanly) sorted and labeled.

Today tried to get the rest of it done, not so lucky. Belts off, cam covers off, cam belt off, cam belt back plate off and cams out, oil drained. some of the head bolts are very very stuck though. Snapped the socket extention and bent the ratchet itself (thankfully had a good socket on it!!).

Any suggestions on getting these to budge? I've had a pipe of the end of the rachet up to about 50cm and still they woudlnt move (and I really dont want to snap the heads off the bolts thats for sure!!). Im a bit hesitant to go spraying crc into the head, and heating it up seems like a recipe for a fire and/or warped head. Any ideas?

[pc]

I use a good socket with a good extension and then put a 1.5 foot breaker bar on it. You will need good gear otherwise it will break... It may break anyway, But I haven't had any break on me yet taking out head studs.

[rollaholic]

yeah ratchet is not a good idea, get half inch drive stuff and a power bar as mentioned above.

[ChaosAD]

A 10mm 1/2" drive socket wont fit in the head. a long socket MAY fit but the standard ones dont seem to.

Youll need a 10mm doublehex 3/8" drive socket and extention, then get a 3/8-1/2" reducer and get a decent 1/2" drive powerbar on there.

Ive usually found after replacing the headgaskets that the rings are stuffed, but it should still go alright.