Seized engine!

[Steve83]

Yeah, it looks like you've got friends in high places! The screw got the worst of it - it usually doesn't work out that way!

 

[slabghost]

Piston looks serviceable but I'd sand off any high spots as they will retain a higher heat and may cause preignition.

 

[Ansimp]

+1 on clean up the piston, even scraping with a small wood chisel.

 

[Write2Paul90277]

Hi guys,

Well, I've got the bike back together after installing an undamaged cylinder head off eBay. I used new gaskets, quadruple checked the manual every step of the way, felt pretty confident about the whole process.

Upon completion, the bike fired right up, but within seconds the garage was filled with thick white smoke (Arrrgh!!)

The next unpleasant surprise came when I saw coolant sputtering out the exhaust drain hole (at the junction of the header pipes and the muffler).

About the only positive sign is that there doesn't appear to be any coolant in the oil. (Gotta be grateful for the little blessings, eh?)

So… where did I go wrong??

Many thinks in advance,

Paul

 

[Steve83]

If you're talking about the hole that goes through the head from the spark plug well to the exhaust port, there's only 2 ways for coolant to come from it: It's leaking into the spark plug well from an outside source, then through the hole, or the head is cracked and leaking internally into the drain hole, and either into an intake port or combustion chamber. Do a compression test, and maybe remove the intake horn from the cylinder with the leaking hole and look for coolant.

Is it the Ebay head, or the original that's leaking?

 

[Write2Paul90277]

Thanks Steve,

It's the eBay head that's leaking the coolant into the exhaust, or at least I should say that the coolant is coming out of the muffler on the same side as the suspect head.

I did a compression check -- all 4 cylinders are around 180-185 psi.

There were no visible cracks in the eBay cylinder head. It supposedly had around 50,000 miles on it. The bike itself has only around 23,000 -- it's been so long I don't remember the actual number!

Help me out here -- I'm not sure what you mean by "the hole that goes through the head from the spark plug well to the exhaust port." I'm assuming you don't mean the little drain hole at the bottom of the spark plug well that allows rainwater to drain to the ground, right?

Of course, there are oil and coolant passages galore between the cylinder head and the engine block, but I took all sorts of care to use new gaskets (genuine Honda) and O-rings, and made sure the head was torqued to factory specs.

Anyway, the whole thing has be discouraging because I had a practically "new" 84 Aspencade that, thanks to one dropped screw falling into the combustion chamber, is now totally unrideable. Waaah!!

Thanks for listening,

Paul

 

[dan filipi]

Just for clarity, coolant is coming out the exhaust tail pipe end or at the header pipes below the head?

 

[joedrum]

the 1200 heads have air channel in them that puts sir in the exhaust ...if the head cracks there it could put collant in the exhaust i am thinking

 

[dan filipi]

Yes that's what I'm concerned with.

This is a 1200 exhaust port I had that very problem and how we originally discovered the possibility.

If you pull the exhaust off that leaking side and look up in there you should be able to see a steam cleaned area.

 

[Steve83]

The rainwater drain hole is the one I was referring to, as I thought it was the one you were talking about. I re-read your post, and now I'm not sure which hole you mean when you said, "The next unpleasant surprise came when I saw coolant sputtering out the exhaust drain hole (at the junction of the header pipes and the muffler).

Joe may be on to something. Maybe drop the exhaust headers on the bad side and start it. If white smoke comes out the port(s), coolant is getting into the combustion chamber. If coolant drips out of the port(s), it's turning to steam in the hot exhaust pipes. Either way, the head will probably need to come off.

Sorry, Paul, his sucks! It is discouraging, but hang in there - the final results will be worth the effort.

-Edit- +1 on Dan's post as well.

 

[Ansimp]

As much as I like eBay it can be a way for the unscrupulous to sell scrap for a pretty penny...

 

[Write2Paul90277]

Hi guys,

Well I am now officially giving up! (See thread above).

Coolant is still leaking into my #3 combustion chamber and creating huge clouds of white smoke. I can't tell if the oil is contaminated this time, but it last time it turned light brown like chocolate milk.

Where did I go wrong?

I went through the whole process again, using another cylinder head with freshly ground and lapped valves. I even had the head milled lightly to assure a totally flat surface.

I used a new, genuine Honda head gasket, torqued the head to factory specs, buttoned everything up and started the engine. It started instantly, ran smooth, idled evenly, pulled strong during my test ride, but... DANG!!!!… there's that sweet-smelling white smoke engulfing the neighborhood again!

When I got home, coolant was dribbling out of the drip hole between the head pipes and the mufflers.

The only other causes I can think of is either a cracked piston, a cracked head, or both.

What I have now is a practically new (23K) GL1200 with a useless engine.

Any thing I'm overlooking here? Anyone got a low mileage motor for sale? (Seriously)

Thanks for listening. Again.

Paul

 

[joedrum]

it is as i said in the thread ...the head you got is cracked in the stupid epa air channel in american gl1200s ...this was stupid as can be but thats all it is ...it is very bad you got stung by ebay and epa engineering... but it sounds to me you got a very good lower end ... seems to poured rain twice on you .... you really just need a good head is all with gasket and recharge to do it after all the BS ... im sure ive got one for 1200 as i dont use them on my builds ... cheer up

 

[joedrum]

if you look at the plugs and the number 3 plug dosnt look stream cleaned then id say for sure it is cracked head in the air channel on that cylinder

 

[dan filipi]

joedrum » 2 minutes ago[/url]":i6vlxpai]
if you look at the plugs and the number 3 plug dosnt look stream cleaned then id say for sure it is cracked head in the air channel on that cylinder

I was able to see up into the exhaust port which got steam cleaned from the coolant.
Worth a check before pulling the head.

This is a pic from the valve head side but I was able to see the steam cleaned metal from the exhaust manifold side.

 

[AApple]

I've read this thread 4 times now. I see nowhere that you said this thing was running well before the mishap of dropping the screw down into the plug hole. You DID allude to overheating by running with no coolant, but not clear on if it was on this bike or not. So we don't know if there was a problem before the screw debacle. :blush:
A couple of questions:
1: How long did you run this thing after replacing the head the first time before it started blowing steam?
2: How long after the second head replacement?
3: Did you remove the exhaust from the bike before pulling the head, or just drop it down?

I'm gunna throw this out there, and ya'll hear me out....is it possible that the steam/coolant coming out of the pipe is from coolant running down into the head pipe/muffler from pulling the head? Just a thought.... :BigGrin: Of course, if the exhaust was completely removed before pulling the head, then that idea is a wash-out.
(I did not remove the exhaust on mine when I did the heads..just loosened and dropped them down far enough to get the heads off.)

Is the EGR passage thingy cracking a common issue on the 1200 heads? Seems strange to get two different heads with the same problem, tho it is certainly possible.... :headscratch:

 

[dan filipi]

Crack in the port is very un-common.
In fact mine is the only experience I'm aware of.

 

[Write2Paul90277]

Thanks everyone for your careful consideration in diagnosing this thing.

Yes, the bike was running perfectly before the %#@*^!! screw fell down the spark plug hole.

In answer to your questions, AApple…

1. Ran it for about 5 minutes. It started blowing steam immediately
2. Same thing the second time.
3. I removed the entire exhaust system, and flushed out the coolant residue with acetone each time.

And yes, I'm curious too as to whether or not the air passage problem is a common occurrence on other 1200s.

Inquiring minds want to know!!

Best,

paul

 

[joedrum]

i was under the impression both head gaskets blew on the same ebay head ?

 

[Write2Paul90277]

Hi joedrum,

Actually, no head gaskets ever blew. I just pointed out that every time I had the head off, I always used a new, genuine Honda head gasket.

Thanks,

Paul