Head Gasket pre-testing


Information and questions on GL1200 Goldwings (1984-1987)
  • Sponsored Links
User avatar
SilverDave
Posts: 367
Joined: Sun Aug 09, 2009 9:39 am
Location: Langley, BC
Motorcycle: 1985 GL1200 GoldWing Aspy

Head Gasket pre-testing

Postby SilverDave » Mon Sep 17, 2012 10:36 am



I am pretty sure from all the symptoms that its a blown head gasket on my 1200:

- explosive boiling over of the antifreeze, thru the overflow tank
-mist and steam everywhere
-off scale temp readings for about 5 minutes after shut-down
and :
nothing found wrong in fan switch, rad, thermostat, pressure cap, etc...

but.... before I start the strip down to new head gasket(s)

1) Is there a pre-test one can do on a 1200 engine to confirm head gasket failure ?

------------------------------------------------------
and 2) Does anyone have any opinions, good or bad , on this gasket kit , from SledPartsGuy ?

http://www.ebay.com/itm/Honda-GL-1200-G ... 6rk%3D2%26

SilverDave



User avatar
thrasherg
Posts: 1838
Joined: Tue Oct 20, 2009 11:21 am
Location: Plano, TX
Motorcycle: 2004 GL1800, 2005 Honda Shadow 750, 2008 Yamaha R6 with RG500 engine, CRF450X, CRF230, CRF250X, XR200, CR500

Re: Head Gasket pre-testing

Postby thrasherg » Mon Sep 17, 2012 3:11 pm

Based on your description (explosive boiling over) it would sound like the head gasket has failed between the cylinder and the cooling jacket, therefore a standard compression test will identify the cylinder with the fault. You can purchase a compression tester cheaply from any car parts store then unscrew all 4 spark plugs, screw the compression tester into one cylinder, make sure the kill switch is in the kill position (You don't want any sparks) then hold the throttle wide open and hit the starter button. Let the starter crank the engine for 5 seconds and then read the compression gauge. Do this for all 4 cylinders and you should see 1 or 2 cylinders with a much lower reading than the others. Those are the ones that have lost compression (Probably the head gasket). Then you can start to remove the appropriate head and replace the gasket. You will probably need a 12mm spark plug adapter for your compression tester..

Hope that helps.

Gary

User avatar
feetup
Posts: 100
Joined: Mon Jun 29, 2009 1:15 pm
Location: West Coast of Canada
Motorcycle: 84 GL 1200I
75 GL 1000 (in pieces)
'02 Gas Gas Trials
'56 Norton 600

Re: Head Gasket pre-testing

Postby feetup » Tue Sep 18, 2012 3:17 pm

Thrashberg is correct. The symptoms clearly indicate head gaskets.
I would not crank for a full five seconds for a head gasket check, but I'm sure it will do no harm.

It is almost assured that if only one head is leaking the other is about to. The free standing cylinders on these engines are great for coolant flow, but not so good for aging gaskets. It seems that head gaskets are the new Achilles heal just like the stator.

As far as aftermarket head gaskets go there are some really poor ones out there. I had a set of aftermarket gaskets go less than 10 months after installing them. The gray (graphite?) filler material that formed the bulk of the gasket seemed to be eaten away wherever it made contact with coolant. I will state that I was using a coolant additive called "water wetter" but have used it in other engines with no problems.
I would not gamble but spend the money on genuine Honda parts, at least for the head gaskets. If you sift through all the goldwing forums there are many instances of aftermarket head gasket woes.
These are relatively easy heads to do, but it is vital that you do everything with surgical cleanliness and care, check your heads for flatness or have it checked at a machine shop, check your block as well, and I would advise that you use new locating dowels as well. They tend to corrode and will hang up the gasket and head and could easily give you false torque readings if damaged of rusty.

Don't forget the little 6mm bolt underneath the head. There have been broken heads out there.

User avatar
SilverDave
Posts: 367
Joined: Sun Aug 09, 2009 9:39 am
Location: Langley, BC
Motorcycle: 1985 GL1200 GoldWing Aspy

Re: Head Gasket pre-testing

Postby SilverDave » Wed Sep 26, 2012 8:24 pm

..... well I compression tested all four cylinders, and they were all within 10% of each other.... very slight improvement with a tsp of oil... so tired rings, maybe, but not obviously a head gasket...

I am now thinking it may have overheated because of a low rad level... Apparently GL1200's do not create enough suction to suck fluid from the overflow tank if they are down a cup of antifreeze... who knew ??


Furthur tests are certainly in order before I wade into the heads ...

SilverDave

User avatar
feetup
Posts: 100
Joined: Mon Jun 29, 2009 1:15 pm
Location: West Coast of Canada
Motorcycle: 84 GL 1200I
75 GL 1000 (in pieces)
'02 Gas Gas Trials
'56 Norton 600

Re: Head Gasket pre-testing

Postby feetup » Thu Sep 27, 2012 9:41 am

Just went back and re-read your original post.

Does the explosive boiling over happen every time or did it happen just once?

If you severely overheated it once, it would not be unlikely for the head gaskets to be toast.

If the coolant was low enough for the engine to overheat that way, where did it go?

With the engine running, the rad full and the rad cap off do you get a continuous bubbling of the coolant in the radiator neck, which gets more intense after you blip the throttle?

Most of all, do you smell glycol in the exhaust after you first start it from cold?

It is untrue that these cooling systems will not draw coolant from the overflow tank. If the rad cap is defective, or the radiator neck dirty or damaged they would rather suck air as they cool down and the coolant contracts, or if there is a crack or pinhole or other air leak in the overflow hose or for that mater anywhere in the system, including the head gaskets, but with a healthy tight system they have no problem keeping the rad full. I doubt they, or any other cooling system will draw a cup of coolant in one heat/cool cycle but they will keep the system full.

Because of the design of the cylinder block and head gasket they will sometimes run fine when warm, but weep coolant into the cylinders as they cool down. I made a light which was nothing more than a mini mag light bulb soldered and shrink tubed to the end of some twisted solid core bell wire, the other end connected to the mag light body. I was able to insert the bulb into the cylinder through the plug hole and see a small amount of coolant lying in the bottom of the cylinder, against the piston crown. You have to peer closely, but with the room darkened and the inside of the cylinder bright it is amazing what you can see. One could always insert a long wooden Q tip, the type used by doctors and chemists through the plug hole and wipe the bottom of the cylinder to check for glycol. Don't break it off in there though!!! :shock:

I know of no other diagnostic tests for a head gasket failure.
- Compression check (probably the least revealing except for a completely breached gasket.)
-Presence of bubbles in coolant
-White smoke or steam on start up, smelling of glycol
-Constant loss of coolant, not evident in overflow tank.
-One or more spark plugs showing cleaner than others, damp after cold, switch off cranking.
-Inspection through plug hole reveals wetness, and clean piston crown

User avatar
SilverDave
Posts: 367
Joined: Sun Aug 09, 2009 9:39 am
Location: Langley, BC
Motorcycle: 1985 GL1200 GoldWing Aspy

Re: Head Gasket pre-testing

Postby SilverDave » Thu Sep 27, 2012 5:17 pm

Feetup:
no... just once with the explosive boiling , certainly not every time ...

and there are a lot of negatives in this sentence of yours :
<<If you severely overheated it once, it would not be unlikely for the head gaskets to be toast.>>

meaning : in your opinion
One single overheating would not cause the head gaskets to blow out ??
ok
some faint hope, I guess....


I have not smelled hot glycol, or seen any smoke last several months...
and (sadly) I have not checked the rad level for at least a year... I was relying on just the overflow tank, I guess.
All spark plugs looked the same .... I see no obvious leaks in overflow hose, or top and bottom hose , no in the overflow tank either.....

I am going to get a new rad cap to go with the new thermostat, and cobble it all back together... probably with just water... and fire it up, and check for bubbles.....


Heavy Sigh ...

SilverDave

User avatar
feetup
Posts: 100
Joined: Mon Jun 29, 2009 1:15 pm
Location: West Coast of Canada
Motorcycle: 84 GL 1200I
75 GL 1000 (in pieces)
'02 Gas Gas Trials
'56 Norton 600

Re: Head Gasket pre-testing

Postby feetup » Thu Sep 27, 2012 5:34 pm

Hey Siver Dave,

You may well have dodged the bullet. One can always be optimistic any way.

Good compression, no glycol smell. These are good signs.

Check the overflow hose for cracks and tight fitting ends, and as you say change the rad cap. Napa has an alternative cap, but I'm not sure of the number. It might be on this site or on the Steve Saunders or the GL1200 site.

Using plain water you won't get the glycol smell but you have to test things and it would be a waste of glycol if you have to tear it down .
If all is good and you drain and fill with 50/50 mix many advise to use distilled water from the drug store. It's cheaper than bottled water and certain not to have chlorine or minerals in it. I see by your address that you live in a country of good tap water but it will still have chlorine in it and aluminum alloy really hates chlorine.




Return to “GL1200 Information & Questions”




Who is online

Users browsing this forum: No registered users and 1 guest