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Temporary Gaskets

4K views 13 replies 7 participants last post by  tbpmusic 
#1 ·
have you guys ever tried an "exacto-ed" pizza box. i've heard if your in a jam it'll work. that said, i used a kind of thicker brown cardboard chinese food container yesterday i had out of the trash from Whole Foods and well... my engine is COVERED in oil. it was for the exhaust cam cover -at least i'm really hoping that is where all this oil is coming from. again, post on my rebuilt frakensteined engine coming soon, but just curious about the gasket thing. any other ideas out there about using something in a pinch? and YES my gasket is on order

ps. anyone know of the PERFECT bush to clean in between the fins of a 450 engine? i mean, to get REALLY deep inbetween the fins. ;)
 
#3 ·
Buy gasket paper at an auto parts store. you can make permanent gaskets out of it. It's a good thing to have around in case you need a gasket you don't have and it's midnight Saturday... As far as card board goes, the material used in pizza boxes is often treated to be somewhat oil resistant (for obvious reasons). Most solid cardboards (not to be confused with corrugated paper, the stuff usually used for "cardboard" boxes) would permit no more than a bit of oil seepage, but you may be taking a chance using them - Their material is not, after all, engineered to be motor gaskets.
 
#4 ·
#5 ·
duh...


thanks guys, got the exacto knife and hole punch out now! i'm determined to get on the road today.

and steve, where can i get a bore brush? i know of ZERO gun shops around me...
 
#7 ·
Is there a Cabella's, Dicks Sporting Good or anything like that around you??
Anyplace with a decent sporting goods department should have them.
Sometimes auto parts places sell them as cleaning brushes for oil passages too.
Or, steal it from your buddie who reloads. :mrgreen: :twisted: ;)
 
#8 ·
Because you don't seem to be familiar with making gaskets, I'm copying something I wrote some time ago on how I make them. I very seldom buy ready-made gaskets - the gasket paper is cheap and the gasket sets aren't. And my "plan ahead" quotient isn't very good.
Getting screws out: I use a 3/8 air impact with a #3 Phillips bit set for fairly soft impact torque and let it rattle away at the screw until it comes loose. Setting for high torque has a way of demolishing the screw heads right away as does putting a lot of pressure on it with a leveraged screw driver (like with a Vice-Grip pliers attached to the shank).
For case cover gaskets you don’t have to buy ready-made gaskets at all – they’re easily made, and I make extras when I’m making them for future use. The ones I make seem also to be more durable than those supplied in gasket kits.
Always start by making sure the cover for which you’re making a gasket is flat. Setting the sealing surface down on a piece of emery paper placed on a perfectly flat surface and moving the cover around on it will polish the high points. They’ll have to be filed flat. Use a single cut file – much smoother surface, easier to file things perfectly flat. High points will be around the screw holes.
I don’t remember the thickness of the gasket paper (haven’t had to make them for a while), but I get a roll of gasket paper from the local auto shop. I set the cover for which I need a gasket down upon it and trace the outline of the cover, then mark all the screw holes with a scribe, poking small holes at several points on the circumference of the hole. Taking the cover off the gasket material, I use a compass (tool for drawing circles) set to the width I want the gasket to be and follow the outside line with the point, using the pencil to draw a line for the inside cut. I use a large gasket punch (any small round object will do, but I can see where I’m setting the punch through the hole in the side) set over the screw hole marks to draw the cut line around the screw holes. I use a smaller gasket punch aligned with the scribe pricks to punch out the screw holes.
Carefully cut along the inside line with a single edge razor blade or (better) a craft knife, being especially careful around the screw holes. I radius the turn into cutting around the holes, and I actually draw a line for that radius before cutting. Cut those first: the gasket material is more rigid then, making sharp curves easier, and it’ll save you from the error of cutting off the mounting hole part of the gasket.
Save the cutout piece for smaller gaskets, often best made by marking the outline of the covers then re-constructing the damaged gasket to fit that outline and marking the inner borders of the gasket.
Where possible, I cut the outside of the gasket with a pair of sheet metal shears leaving a considerable margin of perhaps ¼ to 3/8 of an inch. This gives me material with which I can hold and position the gasket, and – anyway – the method is easier than trying to cut precisely a large narrow gasket (although it’s necessary for a few things where the gasket can’t be trimmed after installation). I install the component with the gasket in place, tighten it down, and then trim the outside edge of the gasket to match the case with a single edge razor blade.
I tailor the gasket compounds to what I want the gasket to do. Consider whether you’ll want to take that cover off and replace it without any fuss or it isn’t going to came apart again ‘til you’re doing a complete motor rebuild and you’d really rather it didn’t leak in the meantime. Some things, like a side cover or valve cover I’ll use a “permanent” gasket seal on one side of the gasket and a “removable” seal on the other to avoid one half of the gasket coming off with the cover and the other half trying to stay with the case.
Incidentally, I’ve found using a cork/rubber compound gasket material, even though it’s marginally thicker, works nicely for the alternator rotor cover. I only use gasket compound on one side of that, and get no leaks.
Most covers aren’t highly critical about the thickness of the gasket, but a few are. The covers over the camshaft ends determine camshaft end play and have to have gaskets of a precise thickness.
Over tightening screws probably won't stop the covers from leaking and may well be the reason they leak in the first place. It can also damage the threads in the motor case, which can jam the screws in place making them very hard to remove - and compromising their ability to be screwed back in. Aluminum is pretty soft stuff, and none of the screws have to be any tighter than you can get them with an ordinary screwdriver.
 
#9 ·
on the subject of screwdrivers, have you guys ever noticed that regardless of #2, #3, or whathaveya, it never seems to fit the screw properly?


American Phillips screwdrivers have a different taper in comparison to their Japanese counterparts. Out of necessity, I've located myself a set of "Japanese Taper" drivers for my job, and its a night and day difference when using them on my old Hondas. It's definitely worth searching the interweb for your own set.
 
#10 ·
great tips Kerry...

i pretty much followed the same process on my exhaust cam cover and the right side cam (tachometer) gaskets. i wasn't aware that thickness played a role in cam gaskets. i'm using some relatively thick stuff for that right side cam, but it really seems to be doing the trick and i haven't noticed anything else out of whack. what should i be looking for? additionally i purchased a left side lower case gasket (you know, the biggest one down there, not behind the generator, but the next one in...) and it SUCKS! it's leaking all over the place. i plan to cut one myself but there goes $16 out the window. i'm sure my screws are tight, i just really believe the gasket is crappy (its probably not). with the success i've had on making these others i am a convert. i will probably never purchase another gasket ever again.

this board is INVALUABLE to a new 1971 honda bike mechanic.

shiney-oily engine pics, and one to prove i'm finally on the road! awesome 20 mile ride to work today.




 
#11 ·
uhohferris said:
great tips Kerry...

i pretty much followed the same process on my exhaust cam cover and the right side cam (tachometer) gaskets. i wasn't aware that thickness played a role in cam gaskets. i'm using some relatively thick stuff for that right side cam, but it really seems to be doing the trick and i haven't noticed anything else out of whack. what should i be looking for? additionally i purchased a left side lower case gasket (you know, the biggest one down there, not behind the generator, but the next one in...) and it SUCKS! it's leaking all over the place. i plan to cut one myself but there goes $16 out the window. i'm sure my screws are tight, i just really believe the gasket is crappy (its probably not). with the success i've had on making these others i am a convert. i will probably never purchase another gasket ever again.

this board is INVALUABLE to a new 1971 honda bike mechanic.
K4's had a chain-oiler thing in the end of the countershaft that puked oil out all over the place - make sure that's not your problem.
Also, the rectangular rubber grommet that goes around the stator wires as they exit into the countersprocket area can also leak.......

A too-thick (or too thin) cam cover (bearing) gasket might affect your cam sideplay. Consult your manual for specs.
And the clutch cable goes inside the left carb, not outside like you have it........

Pretty unusual taillight - looks just like a helmet ..... :lol: :lol: :lol:
 
#12 ·
Glad to see another 450 is back on the road after a little rest for a few years! ;)

I don't know what it was called but there used to be a specialty gasket paper available that swelled a good amount once it came into contact with oil. That stuff made the best gaskets ever! My dad and I used to make gaskets for all of his autos and our lawnmowers as well. Hardly ever leaked if done properly.

GB :mrgreen:
 
#13 ·
thanks bill.
1. i'll re-route the clutch cable. i never really know what to do with it.

2. so the cam bearing cover gasket is 1/32", at least it says so in my previous pic. off the top of your head does that seem like it WOULD in fact screw with my cam "side-play?"

3. any other details as to where i'd look for that chain oiler thing? and yep, i had to remove the cover 3 or 4 times to get that stator wire rubber piece in the correct place.

and GB, if you think of that gasket paper i'd be interested to know...
 
#14 ·
uhohferris said:
thanks bill.
1. i'll re-route the clutch cable. i never really know what to do with it.

2. so the cam bearing cover gasket is 1/32", at least it says so in my previous pic. off the top of your head does that seem like it WOULD in fact screw with my cam "side-play?"

3. any other details as to where i'd look for that chain oiler thing? and yep, i had to remove the cover 3 or 4 times to get that stator wire rubber piece in the correct place.

and GB, if you think of that gasket paper i'd be interested to know...
1) There's a clip that goes on one of the tappet access cover bolts to hold the cable in place and keep it out of the way of your choke and throttle cable.

2) No way to tell - you just have to measure the camshaft endplay as outlined in the Manual.

3) The chain oiler is actually in the end of the countershaft, right in the center of the sprocket area, you'll see it once you clean the area up - look at the fiche. It's notorious for puking huge amounts of oil. Some guys plug it up, some (like myself) actually replace the countershaft entirely with one from a model without the oiler. I believe the oiler was only present on K3-K4, but might be on K5 also - anyone???
I generally resort to silicon on that grommet - not much danger of plugging up any oil passages there.
 
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