Is my head gasket leaking?

So after my ride home from work, I checked out my engine and was VERY pleased to see no oil leaking from my valve cover. New gasket and donuts seemed to have fixed that, and there isn't oil on my pants LOL!

It looks like my head gasket is leaking a bit though. I dunno, I snapped a pic to see what you guys think. That's a big job changing that right?

There was definitely oil right at that head gasket... But the bike runs fine (I do have to throttle it for a good 5 seconds to get it going from pushing the start button, but I think that's unrelated to head gasket leak)

Anyways.. what's your take?

 

I'd it looks like a head gasket to me, but I've been told there are drain holes from the spark plug wells that come out around the head gasket area and give the appearance of a leak when there is none.

Is the area around your plugs clean?

Im not super knowledgeable on bikes, but I work on cars for a living, and I know that an easy way to double check that a gasket is leaking is to clean the shenanigans out of that area, then run the engine for a while, come back and look at that same spot. You can usually see if fresh oil has accumulated, or if it may just be collecting there from a leak at another spot.

And a side note:
Looks like you got some hefty cracks on your intake boots. Have you had any trouble with vacuum leaks?

 

rookie here...
Like kj said clean it off and check again for leaks. The bottom half of the motor if I'm not mistaken should be painted black. And if it were a head gasket you should be able to check it with a compression check. Oil can leak from anywhere and it comes down.

Check the cracks on the boot's.

Just a thought double check your yics bolts make sure it tight.

 

clean thoroughly and apply talc, ride again then inspect

 

Looks like the Head Gasket IS Leaking.

Clean the area thoroughly.
Blow some Baby Powder right where it looks like the Lead originates.
Get an idea of how big the Leak-point is.

This far into the Season, ... I'd try a Torque-check.
Loosen the Head Nuts in the right sequence.
Do one at a time.
Lube the Acorn Nut and brush some Lube on the Threads.
Tighten to Specs.

50/50!
The Leak might diminish or stop.
Might very well not.
If it works you might not have to pull the Head and avoid the down-time this season.

2-Cents worth.

 

Rick and everyone, thanks for the input. Sooo I've got 500 into this and I JUST got it.... It's been sitting more than riding. Head gasket is tough to replace?

So how do I loosen the head nuts? Where the heck are they? Take them out and lube the acorn nuts? Sorry this is all new to me! What kind of lube should I use?

Also, if you are talking serious downtime, I may just cut my losses and be out about 600-700 bucks, I just don't have the money to keep throwing at this thing.

 

How do you guys recommend I clean this area? I soaked it once in engine degreaser and rinsed off, didn't do much...

Damn, if this is another 2-300 dollar repair I'm out. I've sunk so much into this already... And have only ridden a few hundred miles.

Oh and the intake boots? I dunno, the bike runs. I have to crank the throttle while pushing the start button, but once she's on she runs well....

Those things are like 40 bucks a pop, will have to wait until I get the balls to clean the carbs. But again, if the head gasket is blown... that seems like a big job and I have no garage and only a temp space that I can use once in a great while... I've got 200 more in parts on the way... ugh... disheartening to say the least.

Can you tell me what the Yics bolts are? And the baby powder? what will that do?

 

I hate to be a wet rag, but. . .
You did buy a 30+ year old bike for a good price. Chances are really good that every component on the 30+ year old bike is the same age as the bike.

You WILL be putting money into it to make it reliable and safe.
You MUST replace key components on your bike for it to be safe for YOU. This means checking your rear brakes immediately!
You really should get a manual for the bike, there is a lot of knowledge here but having a manual empowers you to do even more without waiting for a reply.


Patience and a small investment (compared to buying a brand new bike that has all brand new parts on it) will reward you with the joy of having one SWEEEET ride.

 

"YICS bolts" are those bolt heads on the side of the cylinder head right where it meets the head toward the rear, yours look fine in the pic.

The oil you're seeing may be the head gasket; or it may simply be residual seepage left over from your valve cover leak.

The baby powder can help reveal the source of the leak ONCE the area has been thoroughly cleaned.

Replacing the head gasket isn't horribly complicated or uber-expensive; but it does involve pulling the head which isn't necessarily something you want to do without a workshop environment of some sort.

But don't jump to conclusions. DIAGNOSE. Use a citris-based engine cleaner from the auto parts. Read the can, be sure it says it's for use on COLD motors. (These products differ.) Clean the motor thoroughly; not only there but in the spark plug galleries, the front of the block, etc. Get it CLEAN.

Then you can dust it with baby powder if you like; it probably won't be necessary. If it's leaking you'll see oil begin to reappear, baby powder or not.

DO A COMPRESSION TEST. You can "borrow" a compression tester from the auto parts if you don't want to invest the $30.

As far as re-torquing the head, don't just start unscrewing nuts. The bolts need to be loosened in the same sequence they're tightened in; this is covered in the SERVICE MANUAL.

One last point; I'm sure you've been around long enough to have read my advice concerning the budget for a proper recommissioning. I've pointed out over and over to various "newbies" that this IS going to cost between $600 ~ $800 assuming you doing all the work yourself. It will. I don't just make stuff up; I've done this twice so far. THE BIKE will not let you skip over things or take shortcuts to reduce the budget.

Something you do need to invest in is a service manual if you don't have one already.

 

Get a front picture too. Probably not related even if it is a problem, but how's your tachometer hookup? the point is, my 550 tachometer is not clean & probably needs rebuilt so I'm just thinking outside the box

Head gasket change is easy. I've done it more than once between my 650 & helping my brother with his XJ600. Being a kid in my middle 20's I wasn't born & bred to do stuff like this; its just determination. I'm willing to bet you could do the same thing. Do research before you just walk away from it

 

Thanks guys, yesterday was a rough day and I was a little pissed. Fitz, thanks for your reply. I'm more thank OK with putting in 600-800 to refurbish this bike. That'll still put me under 2 grand for a cool little bike. Thing is, I had NO intentions of pulling heads to replace head gaskets, that's the real reason I was pissed. I can do most things between my apartment parking space and works warehouse, but a head gasket? I don't think that's gonna happen.

Fitz, I'll stop and get a citrus engine degreaser, I used that "gunk" stuff before, but I used it on a warm engine. Should I buy that gunk stuff again and wait till the engine is cold?

So when my engine is cold, spray it down, and rinse it off? Any idea how to dry it between those nooks and crannies? The spark plug galleries can get soaked with water no problem?

Oh and here's another thing. My #4 spark plug boot(riders right, I think that's number 4) gets very saturated with oil, however I don't see any oil around the plug, nor anywhere in that little plug cavity.... God I hope this is residual oil, but why would it only be wet right by that gasket?

If the head gasket is indeed bad, will it leak when the motor is off, or only when it's running?

If that gasket was leaking wouldn't the bike run like crap? It idles at around 1100-1300 and has plenty of pickup....

 

If the gasket is leaking out just a bit, it wouldn't have any effect on the engine performance, as long as you have enough compression on that cylinder. The problem is nobody can tell how fast the gasket will go on deteriorate.

I'd follow Rick advice and first retorque the acorn head nuts in the right sequence. I did it once on my XS650 and it stopped the leak.

 

OK cool, is that procedure listed in the Hayne's manual?

I gotta make sure it's leaking from there too.. There's a lot of crud all around there, even above the head gasket... Im just afraid to spray citrus cleaner then hose it off... is that the correct procedure for cleaning these engines? Does it have to dry completely before I can fire it up?

 

I doubt you'll be able to just spray on the citrus cleaner and spray it off. You'll need to get a couple different brushes to scrub all of the surfaces, nooks, and crannies. Then rinse, repeat, rinse repeat, rinse, repeat....

Chances are pretty good that has been leaking for awhile & the oil is baked & aged on there. It took quite a bit of persistence (and beer) for me to get to a reasonably clean state again & I'm still fighting an oil leak too. Pissed all over my leg on the way to work today. :x I guess that's just the old girl marking her territory. :lol:

Good luck!

 

Did you clean the engine after the Valve Cover Gasket was replaced and THEN notice this "head gasket leak"? If you valve cover was leaking, and the #4 plug cap is wet with oil (new or old?) and it's on the right side...that sounds like oil was/is being sprayed on to the plug cap, and the only place that oil can or did come from is the valve over. And oil/water/any liquid in the plug well is going to flow out via the holes in the front or back of the engine (or we'd have puddles of water in those wells anytime it rained).

I see no reason to jump to conclusions at all about the head gasket until you've actually cleaned all of the old oil from the previous leak. If the oil on the plug cap is new (i.e. you are SURE it was cleaned after the valve cover replacement) then maybe your valve cover is still leaking (i.e. something went wrong on the install). There aren't any other gaskets around the spark plug (are there?)

 

The oil gallery passages go thru the outer two studs (front and rear) for the #4 cylinder...........that passage is sealed by both rubber gaskets (between the top of the jugs and the bottom of the head....along with a steel dowel to keep the gasket from collapsing) and special copper crush washers under the head bolt crown nuts.

If you have a leak on the right side of the engine, and the valvecover gasket/end plug "moons" are eliminated as a source of the leak, AND the cylinder compression on #4 is up to snuff (i.e. about the same as all other cylinders), AND re-torqueing the head (correctly) doesn't solve the problem, then either regular metal washers were used under the crown nuts (= leak) and/or the gaskets/dowel pins are bad/mis-aligned/etc. (= leak).

Of course, if you pull off the head to fix a leak in the jugs-to-head gaskets, you'll probably also want to renew the head gasket, and perhaps service the head (i.e. re-face the valves, replace valve stem seals, etc.) while you're that far into it.

 

Len,

Thanks for the reply, if I have to pull the head, the bike is going for sale.. I was really looking forward to restoring this, but had no intentions of taking the entire engine apart. I don't have the means/knowledge/space to do that. We'll see though. I'll try retorquing the head screws (once I figure out what that means) and I'll clean up the engine meticulously to see where this leak is coming from. Would old oil from the valve gasket leak heat up and become slick again?

The moons aren't leaking anymore thanks to you!

Jim

 

Things to do FIRST.

Order a Genuine Yamaha Factory Manual >> specific << to your Bike.
You really should have one.
If for no other reason than you being ably to hand it to someone willing to help you with the wrenching.
A Tech at a Small Engine Shop might be enlisted. He'll have an illustrated set of instructions to follow and solve any problems.
A "Tear-off Number" Bulletin Board posting at a Vocational Tech School is a resource.

If Removing the Head and fitting a New Head Gasket is necessary; get "THE Book".

Head Gasket short-list.
Remove everything attached to the Head.
Pipes. (A bitch). Remove Cam Cover. Pull Sprockets and Chain. Safety-cord Chain. Pull Bearing Caps, Remove Head Nuts and hidden-ones.

I've seen Heads with Oil Leaks come right off in one fell swoop.
Practically fall off.
Others will not come-off so pleasantly.
Followed by putting everything back like it was after you remove and install the New Gasket.
Have fun getting the Header Pipes off.
Get a Book.
Get some Help.
Bring some fliers to the Mobile Canteen Truck-guy to give to Auto Technicians at the many stops he makes daily.

He'll know the guys looking for side-jobs.
He's running a Tab for guys that are behind and can rip through the job to earn extra money for Bills and Christmas.

 

my advice would be, clean it really good and check on it again in two years and see how it's making out

 

There are 12 acorn nuts on top of the head. Let's say those on the front (exhaust side) are numbered from 1 to 6, and those on the back (intake side) are from 7 to 12.

The loosening pattern should be:

1-12-6-7-2-11-5-8-3-10-4-9

You should start by loosening each nut 1/2 turn until all nuts are loose.

The retorquing sequence should be:

9-4-10-3-8-5-11-2-7-6-12-1

Lubricate the bolt threads witn engine oil before starting the sequence. TIghten the nuts in two stages: 1/2 torque value and then full torque value. Recommended torque is 32N-m or 23.1 ft-lb.

THis is what is written in my manual for my 1983 Seca900. I assume this applies to your model and year, but torque values may differ.

EDIT: I actually checked and sequences are the same, as well as torque values for your bike.

 

Only thing that is not clear in my mind is if all nuts have copper washers or only the outer ones (1-6-7 and 12). Drawings in the manual are confusing on that point and the text says nothing more.

These washers may be too thin on your engine.

 

Wow, great stuff here, so when you say loosen, do I loosen all the way out or just some of the way? I don't even know where these bolts are, hayne's manual really sucks...

Check in two years after cleaning the engine? You think it'll go that long? Hopefully by then I'll have a garage then this wouldn't be so bad!

Rick, thanks for the post again... I downloaded a pdf service manual, I'll dig into that tomorrow (forgot it at work)...

Ugh, I REALLY hope i don't have a head gasket leak! What kind of brushes you guys recommend? I went down there with a toothbrush the first time I tried to clean and that didn't go so well. Oh and after I rinse everything off, how do you recommend drying the spots I can't reach? I let the bike idle for 20 minutes last time, I didn't know any better. Probably drained the battery, PLUS it was smoking like crazy!

 

Read carefully, answers are there (I mean, in my post and in your service manual)!

Acorn nuts are on top of the engine, you will access them easily after you removed the fuel tank and zip-tied your spark lpug wires out of the way.

 

Ive got a pic to illustrate what these acorn bolts look like, and I'd say as long as everything is running good, dont loose to much sleep over it being a possible head gasket. Until it gets thoroughly cleaned it will be impossible to tell if it really is the headgasket or just residual oil left from a leaky valve cover.

As far as getting the crap off, I've heard good things about the citrus cleaners, BruceB recommended http://www.homedepot.com/p/ZEP-128-oz-C ... ed6i43VCSp to me, I havent had a chance to try it out yet tho.

And invest in a set of wire brushes and other like tools, you can get them a dime a dozen at stores like harbor freight. They work great for scraping off years grime.

 

Thanks for the pic man, that helps!

So getting a ton of water and degreaser down near the plugs is no problem?

 

Just make sure the drain hole of each plug well is clean by running a properly sized wire in it, so water will drain while you do the cleaning job.

 

Didn't even realize there was a drain hole in there... I'll have to take a better look. So just degrease, brush, rinse, repeat?? All that water won't do any harm?

And idling the bike for 20 minutes to dry it is a bad idea right?

 

These drain holes aren't big, probably not more than 2 mm in diameter (they were approx this size on my MAxim-X). You could have easily missed them.

Pull your plug wires out of the way and zip-tie them before you clean, so they won't catch any moisture.

 

Hosing down the engine with a garden hose (not a pressure washer) with everything installed (no open intake, exhaust, spark plug holes, breather, or oil filler cap), won't hurt the engine one bit.

Idling the bike means running it off the battery, which drains the battery. On a very hot day (think 90-100+) it could even result in over heating because there's no airflow and it's an air cooled engine. If you mitigate those two issues, by hooking the battery up to a tender, and putting a fan on the engine, there should be no problem. Also, reduce the amount of battery drain by unplugging the headlight (or maybe pulling the fuse?).

Others have suggested going for a ride to dry the bike, or even a leaf blower.

 

IDLING for 20 minutes won't dry it.

Use a leaf blower, shop vac in "blow" mode, a hair dryer set on "cold" or compressed air.

 

Pulling the head gasket is not all that complicated, rick laid it out pretty nicely and it’s in your book as well. i was able to do it myself and i am no means a mechanic! Just take your time and follow the book. if all your doing is replacing the gasket it shouldn’t take you more than a day (possibly 2 if you hit some snags). but if it were me and knowing what i just went through when i pulled the head off my bike i would also clean up your valves since you got it off, but this will cost you more time (not riding) but it doesn’t have to cost you a lot of money, i did my valves for less than $25 not including time. a fair forewarning, the head gaskets may cost you up to $100, i would look into buy a gasket kit for you bike, they can be less expensive and they come with alot more than just the head gasket, and new gaskets are never a bad thing! feel free to PM with questions i just went through this a few weeks ago, i had had many of the same feelings you have now (anger, frustration, confusing... and all these lead to the dark side and we dont want that) and its best to have a helper for lining up the new head once to change out the gasket, its good to have another set of hands and eyes. and try contacting other members in your area(check out the members map , link in my profile) if i were closer id help you out for sure, you sounds exactly like me when i was working on my bike. hang in there youll get her running! and yah it might cost a bit more than you had hoped, and you may not be riding as soon as you hoped but youll get there. i spent over $450 after i bought my bike and 2 months before i was able to ride it, and i still ahve some work to do, but its running and rideable.

Oh and gasoline can work really well on removing old built up grease off an engine, put some in a jar with apply it with a tooth brush and a rag, and use a wire brish to get through that hard outer shell of crude.