1985 XJ700 X Looks like blowen head gasket

I was under the impression that the engine is a modified version of the one used in the FZR. One of the mods made was to allow the use of side-draft Mikuni carbs, because the cylinder bank sits more vertically; the FZR has its cylinders canted forward about 45 degrees or so and used downdraft carbs.

There's a site in Canada dedicated to this model (Maximum Maxim-X). Might be worth giving it a gander.

No. Under bucket here, IIRC.

 

Jetfixer,
This head has the little cups that are under the buckets. I could have checked them but I knew I was pulling them off anyway, kept them in order and I hope after my leak test I will at least know the valves are closing all the way.

Looks like the oil is staying put, but I will let it sit overnight and see if any leakage takes place.

Need help on this, I think the PO must have worked on the bike, looks to me like there are no wear marks on the cylinder walls for a bike that has 40K. One or two of the cylinders do have vertical marks but not too bad. There is also no lip on the top of the ring wear mark, can't grip it with a fingernail.

Can you guys see those little dots on the cylinder wall? That is strange unless that is from the oil ring and the bike was rebuilt recently and just not run in.

Two head gaskets? I have worked on different makes of bikes and normally they only come with one. Have to do some research on this, could be why I was having issues with #2.

That has to be a fresh honed cylinder don't you think?

Tried to point out the water mark on #2 when I pulled off the head. Non of the other cylinders had any water issues on or under the gasket.

This also led me to think something was not right with the seal.

Not too much carbon build up, something on the top of #2 but I am going to guess it was from the coolant getting in there and leaving a deposit of some type.

Hope that is not too pic heavy, I keep them in VGA so they will not eat up too much space or loading time.

So, sense I am this far do I pull the cylinders off and re-hone them and check the rings? I would guess the gasket was the issue and I have lots of cleaning to do on the head. There is a bit of carbon on the exhaust side and the #1 intake looks a little oily (no pics of that).

Intake boot 1 & 3 were also loose as in finger loose. good thing I am doing a full or almost full top end check. Any words of advice would be great, thanks.

 

I'm not sure about 2 head gaskets either... the reason I asked about checking valve clearance is because if cams have to be removed to get to the shims knowing if all are in spec then all is good. If not you will need to know clearance see what shim is under bucket the manual should have a shim chart similiar to the aircooled model. Now as to pulling barrels that is up to you caution with the pistons and rings $$$$

 

Hmm - just the one head gasket shown here http://www.yamahapartshouse.com/oemparts/a/yam/5004286df8700209bc788d6b/cylinder
If PO has been jigging about with it (yes it does look like that cylinder was honed in some fashion) - maybe he tried an extra gasket rather than skim a warped head.
Can you check head for flatness? Might need to take to a m/c shop for that.

 

a100man,
You are the second person to suggest that, maybe the PO put two gaskets in there because the head is warped?

I do have a good m/c shop close to me if that is the case and I have access to a good straight edge as well. Not too sure if that gasket is that thick and it just separated when I pulled the head? Just doesn't seem right is all.

As for the leak or wet test all looks good. Nothing from the naked eye test on the oil leaking on the valve side of the heads so that is good. Need to the the stone honing device and the straight edge from my buddy and then back to it. Those dark rings on top of the cylinders is telling me they need a honing. I am hoping that it is just the standard ring set I will need for each piston after that. Lots of carbon needs to be cleaned off from the pistons, head and ports.

 

If you have a NAPA close to you many still have machine service ,they should be able to check your head for warpage.

 

Found the time today to get the jugs and pistons removed. Then did a lot of cleaning, more carbon then I thought. The jugs really need to be honed now that I have them off and can get a better look at them. Seems like the pistons are in good shape and the ring tolerance is .012 on all cylinders, so I am hoping a standard replacement set will work. Jugs ring tops were really full of oil or carbon. Either way it showed signs of age or leaking gaskets or both.

 

Timbox have a close inspection of the wrist pin tolerances. I read this is a weak point on the 5-valvers but found no issue with my own, however my motor had less than 10,000 kms when I had it apart. It could be nothing but while you have it apart easy to see.

 

Slimmy,
Thanks and I will, by hand there was no wiggle but that is just to find major issues. Connecting rods also seem to be doing good. Should be able to get things started around Wednesday and then get to ordering parts once I know what all is needed. This cooler weather is no helping either as you well know.

From the pic that are wear makes on them for sure. Three of them came out with a push of a finger #3 was another story but came out with a 1/2" deep well socket on an extension. Pushed right out with the proper tool and angle.

 

Tim, where in Wisconsin are you, you cheesehead!
It was -3 this morning and a high of 13 today up here near Tomahawk.

 

Tomah, look were the I-90/94 splits, or look for the Cranberry capital of WI...very close to that...population 360!

 

Timbox, how did you clean up the pistons and head so nicely? What did you use?

 

B-12 Chemtool by Berryman, compressed air, soft brass brush and "Q" tips

 

Welcome aboard. You've got this. 40k is nothing for a well maintained xj. If everything checks out upon re-assembly you'll run it for another 40k+ easy.

Gary H.

 

Gary H,

The only thing I have found so far in the pic above is the head gasket may have been leaking on #2. Everything else looks good including the rings, they are still .012 on all four cylinders. Still wonder if the PO just did a top end and never ran it in. Then had the blown head gasket and just left the bike?

Not that I am that cheep but I was thinking only for a moment to use the rings again after I hone the jugs. I would guess this is a bad idea and I just need to order a standard ring set.

Thanks for the encouragement, it will be needed at I try to fit those pistons back in the jugs.

 

I dont know that I even see the need to re-hone. If you do (pics in general aren't the best for determining that) then a pass or two with a ceramic bottle-type brush will suffice. Re-usiing rings is not a bad idea unless you're hamfisted and damaged them when you took them off of the pistons (personally I just leave them on unless the grooves are really crusty.
You will need new wristpin clips. Those are ALWAYS a one-time-use item.

 

Thanks K-moe, I was wondering why not, the rings do look to be in good shape. Yes the wrist pin clips will be on order along with the gaskets I need in the morning. It took a long time today getting the crankshaft to jugs gasket off. I should have picked up some gasket remover, but I didn't have it on hand so I just took my time.

The rings are in good shape, took my time with those as well. I also have a ring pliers on order and that will be here this week.

 

+1.

Gary H.

 

While I am waiting on parts, removed the back wheel to take a look at the brake. Wanted to make sure that the shoe had not separated from age. Looked a little older but not 30+ yrs, so taking a guess that the PO had them changed out. I cleaned vacuumed and then put grease on the pivot to make that a little smother. Enough shoe there for at least a season maybe two. The front pads looked good too, now lets just hope the clutch is in good shape.

Cleaned out all the old grease in the rear gear hub and then applied more grease. The axle was not too bad, cleaned it up with some steal wool, greased and re installed.

Started to take some of the carbon out of the exhaust ports on the head. Lots of that, so that will take some time. Thinking of using a polishing wheel on a dremel to see if that would work. Like I said lots and lots of carbon, more on #1&2 then 3&4.

 

So the head and the jugs checked out at true no warp. I did a little honing and will take a look see what the rings spec out too if I will go any further. I know the standard set is .012 to I think .018 for a tolerance so I will stay within that range.

I wanted to share some about going from POD's to staying with a air box. I got my kit in a while ago and then got talked (lots of reading) in to staying with the stock air box. This is the second set of jests and instructions I have from this company. If the stock main is 100 to 105 by the spec book these people wanted me to do this. The want me to stagger the getting on the bike because of heat.

"The outer cylinders run cooler since they has a direct air blast and a larger surface area to remove heat. The inner cylinders run hotter since they are sandwiched between, don't receive the same airflow, and have less surface area to dissipate heat. Fuel has a cooling property to it, so by flowing a little more to the inner cylinder, it keeps it cooler, increasing engine life. Also, intake flow characteristics are a little different. This is true even with water cooled engines. There is also another benefit to the very tiny difference in fuel flow. Since altitude, humidity, and temperature are not constant, and they have an effect on jetting, by going with the slightest difference, it will allow the engine as a whole to perform best even as those factors change, since it is spreading the average. The only thing better is fuel injection, which automatically changes based on those conditions."

I just thought I would share this with you guys and still stick with the stock air box. The bike came to me with 115 mains and I am guessing that is whey there was so much carbon inside. I will run a K&N filter but a stock air box so have ordered a (4) 105's and (4) 107.50 hoping that this will be the only changes in the mains I will need.