I have a 94 FLSTC 1340, i lost the rear base gasket today. Luckily i noticed it before riding. How involved is this job? Im not bad with wrenchin on my bike but have never taken motor apart. Can i just do rear, or should front and rear be done at same time? Is there any way to do gasket without taking head/cyl all the way off? Might be stupid questions but remember i have never done motor work on a harley, just dont have the cash to bring it to a shop right now. Thanks for any and all info on this problem.

 

Not a big deal if you have the time and mechanical ability. Everything has to "come off the top", except for the pistons and rods, but you will not have to enter the bottom-end, so there is no danger of screwing up engine timing, etc. Just follow the instructions from a good service manual. You will need new top-end gasket sets and yes...I would replace both the front and the rear since you will have to pull all that stuff off the top anyhow.

You need to throw away any new replacement base gasket that comes with the kit....unless it is one of the later metallic heavy-duty gaskets. They (aftermarket) make a replacement base gasket that will take care of the problem. Don't waste your time by replacing them with the stock gaskets. Harley may now make a heavy-duty gasket, I don't know. It has been years since I owned an EVO and did this job, but I did the replacement on two EVO's that I owned.

 

Just what 1550vt said. Shop manual is imperative. I had to do this on my 96 FLSTF. I think Genuine James gaskets has the base gasket you need. Metal with print-o-seal. Goes without saying you will need new head gaskets, etc. I found the biggest challenge was getting the rocker box off rear cylinder with engine in chassis. To make a long story short, when my engine was "built" at the local shop, they scraped the crap out of the base gasket surface on the bottom of the cylinder. I was not comfortable with just reusing as-is. Sent the jugs to machine shop, machinist measured length of cylinders, ended taking .005 of of rear jug to clean up surface and (i think) .003 off of front cylinder to "equalize" length of cylinders. Let me tell you, that .005 off the rear cylinder made all the difference in the world for getting the rocker box in with ease. Also, if you switch to the James gaskets, pay close attention to the torque values as they are different from stock harley.

 

Thanks guys, i'll look online for those gaskets. I have a service manual and feel pretty confident that i can do the job. Another question is, the bike has 45,000 miles on it but the top end was freshened up (rings/gaskets) at 29,000 miles, should i re-ring it or if it looks good just run it??

 

I'd look at the jugs, pistons, etc. and see, but if it was in good running order before...put it back together unless you see something wrong. When the EVO was the most current engine, I've seen the dealerships just replace the gaskets time, after time, after time only. The ones that I had torn down...never even had the original cross-hatch worn out of the cylinders and one had well over 50,000 miles on it. I did have one bored and over-sized once, but it was after a cam bearing had disintegrated and scattered metal shards all through the motor. If it looks good and you were not pumping oil...run it. A compression test before you pull it apart will tell you what condition your internals are in. If the jugs are worn enough to warrant a new set of rings, it needs to be bored anyway and that requires a special jig and somebody that knows what they are doing.

Why was it "freshened-up" at 29,000 miles?

 

Thanks for the info 1550vt, the bike had been gone through by a HD dealership for the small dealership that i bought it from, just happened to notice rings on the list of parts on the receipt they gave me. The bike never burned oil and ran awesome until i shut it off when i noticed the base gasket leak. So hopefully everything will look nice inside. Just gotta make room in the garage and start tearing it apart. I found a Genuine James top end gasket kit for $71, does that sound reasonable or do you know of anywhere cheaper? Thanks again

 

Not to contradict, nor argue, but we use NOTHING but Cometic gaskets here. Their MLS EST units are the best we've used.
With the amount of miles on the bike, I'd look at the lifters as the Moco released a service bulletin at one time, at 25,000 miles to "inspect/replace".
Measure piston/wall and chances are you'll be able to torque hone/re-ring.
Hastings has a great ring pack for that with a moly-faced top ring.
A quick valve job wouldn't hurt either.
Another quick, inexpensive way, to MUCH more power, if looking in that direction, would be to install a Wood W-6, or Andrews EV-27, and re-surface the heads -.060-.070". 75 hp 85 ft/lbs is in easy reach. Guarantee it'll pick up fuel economy, and run smoother once tuned.
Scott

 

Good info there Hillside and if DOG had the money and the know-how (not that he doesn't) the things you mention are what one should consider. I think he is looking for the most economical way to get out of trouble. The gaskets you mentioned, and the ones 1034 suggested would be good choices...I am sure.

DOG...you can just Google "Harley EVO base gaskets" and I bet you would come up with a number of good ones that would work. You will be able to tell if the jugs look badly worn. If you are not sure.....describe as best you can what you see and maybe some of the real pros on the site here can give you some opinions.

Certainly, if you had the $ in your wallet, you could go deeper like Hillside suggested, but if you don't....I bet you can get by with just the GOOD base gaskets. Go ahead and get the new manifold o-rings too....might as well since you will have the manifold off and that is a potential sore spot you can fix while your in there.

Get or rent a good torque wrench. Don't guess at it when torquing down those head-bolts. Make sure you put all the guide-inserts back in the holes they mate with and be careful not to block an oil passage with a piece of gasket...new or old. Base and head gaskets can be put on backwards...if you try hard enough....people have actually managed to do that.

 

I'd run the cometics. Been reports about some of the James stuff. The rest sounds correct for a fix as cheap as possible. Take extra care when pulling the cylinders off of the pistons, and when re-installing them. Be SURE to use a ring compressor and make sure the ring orientation stays the same. Folks 'talk' about 'ring seal'..... I call BS on this one... there isn't any MORE seal when leaving pistons in jugs as when removing them... what is important is to make SURE the rings stay in their position on the pistons.

OP? You CAN do this. Just takes three times as long as you think... double check EVERYTHING. Take cardboard and draw outline of the various pieces, then poke the bolts you remove into that cardboard outline. You will KNOW how they go back. Also, go get a Sears thread restorer kit. Run these (they look like tap and dies) over every bolt and into every hole. Then use blue locktite where required. (i, personally like the locktite that comes in tubes like glue sticks) Clean the studs and blow out the head bolts... make sure to place a drop of oil in each bolt AND under the bolt washer, NO locktite here! Wouldn't hurt to get a small tube of assembly lube and glob a little on the rockers before sealing it all back up. Look THROUGH the pushrods, while out, to make sure they are completely clear inside.

Go buy 2-3 packs of detail towels from Walmart. Use one towel once. Do NOT wash and re-use for engine assembly. Borrow an air compressor. Borrow a ring compressor (and it need to be one for a Harley/bike (auto type will not work). Get the BEST inch pound wrench you can, and a ft lb wrench. Get 6 cans of brake cleaner. Have a good MOCO manual and not a Clymers, etc. Autozone should have most anything you need for rent. Ask ALL buddies about a ring compressor.

Cleanliness is next to Godliness!!!!!!!!

Did I say to take your time? No drinking and minimal drugs while doing this helps too!!!

Do it ONCE and do it correct and do it with Cometic. Scotty's job is to make us WANT more than we have. He usually has some damn good suggestions on that front, but when he says something about a part or procedure? One needs to listen up. He IS correct on the Cometics. Dammit.... I cannot remember WHAT James gasket there was a problem with.... but there IS one, though. The Cometics MAY be a bit more... but where exactly does one want to 'cheap out' on this kinda thing?

You MAY wish to look at some lifters at this time..... your call. I KNOW about being broke, trust me.

 

Just tossing out suggestions, and food for thought, as that combination is as rock-solid, simple, and economical, as one will ever find, for a quick Evo upgrade, IF, one is looking in that direction.
Scott