How do my compression numbers look?

[Tofuball]

OK, I replaced all four intake manifolds and their O-rings, all the O-rings in the carbs, and blasted it all out with carb cleaner while it was apart.

Now the bike will not go over 10mph

It runs like total crap.

I hate this bike.

 

[Tofuball]

Is there anywhere you would recommend that I could send my carbs to have them rebuilt professionally?

The carbs have got to be the problem.

 

[Dave8338]

How does the bike idle? Can you bring the RPM's up slowly? Is it hitting on all four? There is an easy explination for this, we just have to figure it out! I know where you're coming from...I was about to shove mine over a cliff, now I won't part with it! If my list of projects weren't soooooooo long, I'd offer to do the carbs for you...maybe someone else here will. I'm not sure I'd take them to a shop, unless they specialize in older bikes, you'll get them back in the same shape that they got them in, IMHO.

Hang in there...we'll get it figured out, Uncle Mike holds the record for frustration and you're nowhere near that yet. Sorry Mike........

 

[Tofuball]

The bike idles very strangely.

When I turn the choke up all the way into high idle territory it idles at about 1.5K. Then as it warms up and I move the choke down it will idle around 2K or so. Then, after it's warm, I'll drive around and it will idle very low and sometimes stall out.

With no load, I can get the revs to climb moderately fast, but under load its not happening. 4KRPM maximum.

How can I tell if it's not firing on all cylinders?
I think it is. It was before.

Thanks for the encouragement! It's what I need to keep me from just tossing the bike.


I'm just so down because I just have no clue how to get this sorted out without dumping a lot of cash in it or paying someone else to do it.

 

[salty_monk]

Have you synched the carbs? Did you check the valves?

Can't offer much more insight than that, sorry. Keep plugging away though.

Dan

 

[tfb]

Hmm, I'll just chime in with my opinion guys.

Those compression figures are woeful, to be honest. Not only the variation, but with that cylinder at 85psi you're just not going to get it running right no matter what else you do. 100psi is really the working minimum. So fiddling with the carbies etc. is basically futile at this stage.

It is time for a top-end rebuild. I know this sounds like the last thing you want to do, but honestly it needs to be done.

On the good news side, the fact that your cylinders took such a jump in compression when you added oil, says that basically the rings are stuffed. At least your valves seem to be sealing OK. So you *may* be able to get away with only a new set of rings and having the bores honed.

 

[Tofuball]

It is time for a top-end rebuild. I know this sounds like the last thing you want to do, but honestly it needs to be done.

Any idea where can I buy a kit for this? Or do I have to buy all the parts separately?



Before at least I had a top speed of 80 and could commute using the bike. Now it's just useless.

Thanks for the replies.

 

[Nessism]

Parts should be available from a dealer or an on-line dealer. You might want to look up Mark since he has gone through top end the saga...

 

[tfb]

Basically, you'll need a top-end gasket kit, which should include:

1. Head gasket
2. Base gasket
3. Exhaust flange gaskets
4. Cam cover gasket
5. Breather cover gasket
6. Oil passage O-rings
7. Cam tunnel O-ring
8. Cylinder sleeve O-rings
9. Cam-cover half-moon seals

Or you could buy those items seperately, if you don't think you need all of them (eg. if your cam cover gasket is OK and reuseable).

Be careful if you buy an aftermarket gasket kit; you will need to make sure that the head gasket in the kit has O-rings already fitted into it, so that you won't have oil leaking out of the oil-ways that go up the studs to supply the head.

If you decide upon a genuine Suzuki head gasket, try not to let Suzuki sell you a multi-layer steel (MLS) gasket, as they will only be oil-tight on a head/block that is spot-on.

You should also factor in a fresh set of valve stem seals.

The most expensive items will be the 4 sets of piston rings... recently I paid around AUS$70 per set. That hurt a bit, but it's unavoidable. You'll also need new gudgeon-pin circlips (*never* re-use the old ones).

I also paid about $60 to get the cylinder block professionally honed.

All of this is assuming that your pistons and bores are still within acceptable specification. If not, you'll be up for a piston kit and associated re-boring of the cylinder block. Check out the Wiseco website for ideas on prices. You'll be horrified but remember that they come with piston rings, gudgeon circlips, and a head gasket to suit the oversize pistons... so it's not so horrific when you factor all that in.

While it's all apart, at least you'll have the opportunity to dismantle and thoroughly rebuild your carbies while you're waiting on parts, etc. to arrive. You also can take your time de-coking valves and carefully removing old gaskets -- generally preparing everything carefully for reassembly. Whenever I've done a top-end rebuild on one of my bikes (four rebuilds so far, not including a mate's Kawasaki), I've also gone for new air filters and spark plugs, just to be doubly sure that we're off to a fresh start on fresh parts.

Finally, *don't* run-in the refreshed engine with synthetic oil; use a good quality mineral oil to aid the bedding-in process.

I hope that others on the forum here will chime in if they feel I've missed something.

All the best,
Mike.

 

[Tofuball]

Yeeeouch, the Wiseco stuff is $550 American, and I still have to buy more stuff?

Forget it!

A top end rebiuld seems more reasonable, but if I'm far enough out of spec this bike is as good as a parts heap.

I'm going to do a real rebiuld\sychronize on the carbs first, and check the valves once I get my garage clean enough to find my metric feeler gauges, then I'll see how much checking the cams helps.

Is this the top end kit I should buy? http://cgi.ebay.com/ebaymotors/Suzu...004QQitemZ140126010352QQrdZ1QQsspagenameZWDVW

My cam cover gasket is reusable, because it's brand new.

Thanks for the responses!

 

[rustybronco]

Well, I just checked and my charging system is shot too.

Also the big red wire coming out of the fuse box behind the battery gets pretty hot while running.

Seriously, with the charging system shot, the engine needs to be rebuilt, likely with a bit of head work, the carbs need to be rebiult and resynchronized, the body is trashed, turn signals don't work, etc etc . . . I'm not happy about this.

Honestly I'm thinking about just selling this thing

Don't put the cart before the horse, you need to acess all the things it needs first before you go on a buying spree, find out why it has no compression, head gasket, rings, piston to bore diameter, head and jug flatness, do the valves need work, did the ring(s) stick because it was left outside for a year and the valve was open on no. 3 cylinder, varnish, did it over heat, burned piston, ect.????, one thing at a time, it doesn't cost but time to tear down and inspect it and go from there.

 

[Tofuball]

Don't put the cart before the horse, you need to acess all the things it needs first before you go on a buying spree, find out why it has no compression, head gasket, rings, piston to bore diameter, head and jug flatness, do the valves need work, did the ring(s) stick because it was left outside for a year and the valve was open on no. 3 cylinder, varnish, did it over heat, burned piston, ect.????, one thing at a time, it doesn't cost but time to tear down and inspect it and go from there.

I agree, but it does cost to put it back together, and I'd rather commute on 3 cylinders then have another project in a billion pieces in my garage.

I'm hoping I don't have to pull the engine apart.

 

[salty_monk]

Is it possible to free up the rings by putting some oil in the bore & leaving it for a few days?? Just an idea, I've known it work with seized car engines....

Dan

 

[rustybronco]

penetrating oil, leave it soak for a few days, repeat it as necessary and then change the oil before starting it, or a top end cleaner (g.m. used to make a good spray type one).

 

[Tofuball]

penetrating oil, leave it soak for a few days, repeat it as necessary and then change the oil before starting it, or a top end cleaner (g.m. used to make a good spray type one).

I've been using seafoam in the #3 cyl. I also added it to the gas and to the oil.

I'll check it again once I drove it a bit, but now it doesnt really drive

 

[Dave8338]

When you did the compression check, did you use the exact same amount of oil in each cylinder...if so, how much? After re-reading all the posts on this, aside for the dramatic jump in the #3 numbers, this sounds like a valve adjustment issue...to have one cylinder that much out of wack, just doesn't make sense as far as rings go. Which carb feeds the vacuume port on the petcock on your bike? :?

 

[tfb]

Tofuball,

Yes, that kit seems to have all that you will basically need by way of gaskets. There's also a set of valve-stem seals in there, which is great. Bear in mind, though, that that head gasket doesn't have built-in O-rings for the studs where the oil goes up to the head. So when installing that gasket, I would put a smudge of silicone sealant (high-temp. engine stuff, of course) around each of the oil-way holes, before installing the cylinder head.

By all means give the suggestions above a go first, for that low-comp. cylinder. But trust the figures: you have a problem with rings/bores not sealing, and not valves!! If it was valves you wouldn't have had the huge jump in compression that you observed.

Mike.

 

[Dave8338]

Tofuball,

Yes, that kit seems to have all that you will basically need by way of gaskets. There's also a set of valve-stem seals in there, which is great. Bear in mind, though, that that head gasket doesn't have built-in O-rings for the studs where the oil goes up to the head. So when installing that gasket, I would put a smudge of silicone sealant (high-temp. engine stuff, of course) around each of the oil-way holes, before installing the cylinder head.

By all means give the suggestions above a go first, for that low-comp. cylinder. But trust the figures: you have a problem with rings/bores not sealing, and not valves!! If it was valves you wouldn't have had the huge jump in compression that you observed.

Mike.

Agreed...just want to ensure that the "dump er in" method of oiling the cylinders was not used. If they were all treated exactly the same, it is no doubt, the rings!

 

[Tofuball]

Which carb feeds the vacuume port on the petcock on your bike? :?

The same, #3. Do you think it's related?

Tofuball,

Yes, that kit seems to have all that you will basically need by way of gaskets. There's also a set of valve-stem seals in there, which is great. Bear in mind, though, that that head gasket doesn't have built-in O-rings for the studs where the oil goes up to the head. So when installing that gasket, I would put a smudge of silicone sealant (high-temp. engine stuff, of course) around each of the oil-way holes, before installing the cylinder head.

By all means give the suggestions above a go first, for that low-comp. cylinder. But trust the figures: you have a problem with rings/bores not sealing, and not valves!! If it was valves you wouldn't have had the huge jump in compression that you observed.

Mike.

Awesome, thanks! I'll bet the valves are out of whack too though. So I think it's a combination of things.

I'll definitely do the silicone, but I also have a pile of O-rings, if I can find one that fits . . .

Agreed...just want to ensure that the "dump er in" method of oiling the cylinders was not used. If they were all treated exactly the same, it is no doubt, the rings!

I have an oiling can that squirts basically the same amount of oil each time, and each cyl gets two squirts.

 

[tfb]

Quote:
Originally Posted by Dave8338
Which carb feeds the vacuume port on the petcock on your bike?

The same, #3. Do you think it's related?

Three things can happen with the hose that comes off the vacuum port:
1. It will work. :shock:
2. It will leak air, causing #3 cylinder to run lean.
3. It will suck fuel from a pinhole in the fuel-tap diaphragm, causing #3 to run rich.

So is it related? Not likely. You would have to run it lean for an extended period to do damage, and then it would be burning valves that would result -- which is evidently not your problem with cylinder #3.

I'll definitely do the silicone, but I also have a pile of O-rings, if I can find one that fits . . .

Be sure to use heat-resistant O-rings. If you use more run-o-the-mill ones, they'll just go hard with the heat and then leak.