Hello everyone, I recently bought another Bobcat 732 that was advertised as having no compression... When I went to pick it up, the seller cranked the engine over to demonstrate the lack of compression. It was immediately obvious that the compression wouldn't be the issue, rather it sounded like there was no fuel or ignition. They had tried all sorts of things to make it run including installing new carb, new starter, new alternator, new fuel transfer pump, new distributor and all ignition components except for the ignition coil and a few other little odds and ends. I brought the machine home, started looking at it and found that if I sprayed something combustible into the intake of the carb it would fire but die as soon as the stuff was burnt up. So I decided to take the carb out, thinking maybe it needed cleaning. As soon as I got the carb off I noticed something odd, the gasket between the carb and the intake manifold was green and yellow with nutrition information written on it. Turns out it was just a cardboard box someone had sort of cut out to make a gasket with. They didn't even take the time to make the edges nice and smooth, just butchered it with a utility knife and called it good. They had made a few gaskets like this - the valve cover gasket which leaked profusely, the carb to manifold gasket as well as the intake manifold gasket at the head. The cardboard had all turned soft and mushy by now and so there were all kinds of leaks in the intake. I put some fresh gas in it, installed proper gaskets and the machine started and ran perfect! I've used it for a few hours now and it runs great, no issues that I can tell with the hydraulics or hydrostatics either, all in all a great machine! I just thought I'd share what I found, and maybe see what other kinds of fixes that didn't quite work you guys may have come across...
Cereal boxes make good gaskets for intake, oil drain, etc. but I do try to cut them to fit properly, lol.
Wow. Can't say that I've seen cardboard used that way. I have, however, seen bailing wire used in numerous ways beyond the typical uses. Makes you feel better about yourself as a mechanic when you see stuff done that way! Junkyard
I've used cardboard for gaskets plenty of times with good results, but you have to put at least a little bit of workmanship into them. They're just ugly.
I guess I'm old enough that I've seen this done successfully many times. I was even taught how to use a small ball peen hammer to make these gaskets.
Now you went and ripped it, if you'd been careful you could have reused em.
What is the preferred cardboard? Recycled? Cereal box? Parts box? Are Cat boxes the superior choice? Maybe Uhaul boxes? Medical supply boxes? Lol I couldn't resist. I'm on hold for almost 20 minutes now with FMCSA so who knows that I might dream up. This music makes me want to pierce my eardrums with an ice pick! Off topic I know Junkayrd
Same here. While the correct gasket from a factory is the preferred part a well made one from a cardboard box will get you going in in pinch. Like the boss at the shop when I started back in 1970 would say "If you were out in the middle of the Sahara Desert and Rommel was coming over the sand dune to the west" "What would you do?" Now that the original poster found out how easy a fix this was I'm sure he went back to the person he got this Bobcat from and offered to pay him more than the original price, right? I know I would have problems sleeping if I didn't!
My preferred card board is a coors light box. It has the aluminum on one side and the card board on the other. On a serious note, I have actually used card board as well. I use to work on lots of old tractors and some gaskets were obsolete. I rebuilt an old f20 farmall once , it had the rob bearings that were shimmed between the cap and rod. The babbit was worn but material still there. I used bank checks to shim the babbit bearing back to tolerance. As far as I know its still running in parades and shows.
I do like the hammer trick to make them, I carry various rolls of gasket material. Necessity is the mother of invention! Junkyard
My old man used to use cig. cartons or parts boxes. use a hammer and a socket to make the holes and some 3m trim spray for install. Never seen one of his fail.
I've used soda cans to make EGR gaskets or exhaust gaskets for small engines. I keep a roll of Red, black rubber and a roll of cork on my truck. I'll also brush a little black permatex thread sealant on the surface Sent from my iPhone using Tapatalk
I used to use the waxed cardboard that International Harvester wrapped their baler twine with in the '70's and '80's. Not for a head gasket, though.
I'll do almost anything to buy a gasket to keep from having to make one with a razor, hammer, scissors, etc. That is one job that always takes longer than expected, is hard to get right and the gasket always threatens to tear in a critical place at the last second. But I will do it if I have to.
Well no, not exactly, lol! To be honest I've tried to use plain ol' cardboard for gaskets in the past but I've never had any luck with it... I did make my own carb to manifold gasket using actual gasket paper and a small ball peen hammer, worked great, just a bit time consuming but worth it for sure! Over the years I've made many of my own gaskets this way and the results have been good.
When I was a kid my buddy found an old Vespa style scooter with a 2stroke abandoned in the woods. We found it had a bad head gasket. Having no money and no transportation we made a head gasket out of an old shoebox and got it running! We could ride for about 20 minutes before it burned out and then we'd just make another one! Sometimes you just gotta make do with what you have!!
Just for the hell of is in small engines class we made a headgasket out of grey navistar oil pan silicone on a little briggs, ran it on rubbung alcohol for about 15 minutes with an iv drip till the blue flames came out between the jug and head.
In the eighties and nineties, large rolls of "gasket material" in many different thicknesses were cheap and common at auto parts stores, not so any more. Originally they all had asbestos fibers in them, I wonder what fibers they put in gasket material today. I usually glued them to the casting with 3M weatherstrip adhesive, then after they dried, used a small ball peen to cut them to shape. It worked on most anything besides exhaust manifolds. When we took engines apart and the gaskets tore, we would use a buffer to remove the gasket material, breathing in all the asbestos particles.
Absolutely. But they're notoriously expensive...
Maybe raid the Cat dumpster after hours? And to think I just cleaned the back of my truck and threw away several square feet of Cat gasket material! Darn it Junkyard
The pipe fitters still make their own gaskets...try a plumbing supply.
Is it possible to use a Komatsu cardboard box for non metric gaskets?
Repowerguy LMAO!! That may be the best one yet! Junkyard
Just don't try it on a Cat. Hate to think of what a reaction that might cause. Another Chernobyl like melt down!
I thought cheap beer boxes were the backwoods gaskets of choice. I keep a roll of JV127 on the truck and use it all the time. We work on a bunch of random industrial equipment that's obsolete and has to be fixed now. No way the customer would go for waiting 4 weeks for a gasket to get shipped across the pond if the manufacturer is even still in business.
Just hard to convince the boss you have to wait till the beer is drunk before you start to make the gasket!
The best gaskets come from the Genesse Cream Ale boxes... Worked on a classic BMW boxer for a senior level manager at a major national brewery this afternoon...collectible metal beer signs coming. Minor issues, bad clutch cable splitter and poorly adjusted dual BING carbs. Some guys speak CAT and DEERE, I speak BMW Airheads. Verified gas tank venting, plug cap to plug cap verificaion of secondary ignition, ignition module heat sink paste, and finally put the twin max differential vacuum gauge on the bottom vacuum taps. One side was coming on early, poorly adjusted lower cable from the splitter under the tank. All in all a successful afternoon, plus used the JD 450B shovel dozer to persuade a dead hemlock to fall just the right way, with 40' of 3/8' logging chain. Howard Howard
Dam Howard was hoping you would say you also spoke XS400 Yamaha! Been trying to get one of those to run right. Starts and runs fine until it gets warmed up then idle speed drops so low it stalls. Adjust idle a little to keep it running then it will hang up and idle at 3,000 rpm til you drag it down by letting the clutch out in gear just a bit. Carbs are spotless inside. As for Genny Cream back in the late 60's early 70's when first wife went to college outside of Rochester Genny Cream was reffered to as "Green Death".
Hey Ken, if you find the solution to the Yamaha idle, let me know! not that I'll fix it, but just to pass along with the bike.
I would look at valve lash AND we also see a hang on the spark advance. I had a XS400, followed by a XS650 Heritage Special. The XS400 tended to suffer from valve recession. Howard
Hows your carb boots, check with a spray of carb cleaner between the carb and engine, hanging idle is usually either maladjustment or a vac leak. could be a leaking throttle shaft as well. Also worth checking your valve adjustment.