OK. So how many gaskets do I need to use? It had three when I got it. 2 thin and one thick all together.

So now that it is bored to 81.5 do I need all of these..one of these..two of these??????

I' m confused??

thanks

I believe the oem head gasket has 3 layers. Look close at your replacement/ new gasket. Is it 3 layers? I'm not sure about the fl 350, but I know the fl 400 is three layers. Perhaps the aftermarket gaskets are just one layer. What after market gasket set did you buy? The fl 350 guys will know for sure.

Yes it is oem 3 layers

I know you are excited to get it running, but take your time and get it right the fist time. Make sure you break the Engine in. Take the time and drain the tank and fill with fresh premix gas.i beleive you just switched back to a fuel pump. You want to make sure the carb is jetted correctly so the Engine gets the right amount of fuel. Remember the oil is in the fuel. Take your time and it should last a long time.

The original head gasket was multilayer.
I believe all the after market ones are paper not metal.
I have heard here that some have taken the original apart and only used one and someone here actually ran no head gasket (not recommended). The stock Engine has a huge squish clearance. I think I measured 1/8" on mine. Your safe what ever you do.
By the way I am a silicone homo so if I were to run the original gasket I would use one layer and lightly silicone it for safety. Just my opinion. Pressure test this Engine when completed. Don't start it until you do.

A little off topic but it appears you are spending real money and time on this project so in my opinion you better be running race fuel or avgas when this is done. If you don't remember what I have just said here. Your on your own.

I run 92 octane non ethanol and have never had a problem. I ride at sea level and the temperature is typically 60-70 degrees. Why do you say run race fuel on a stock motor (( Internal Combustion Engine ? ))?
Rand built 3 fl350s for me. Maybe that's why I don't need race gas! (-:

The manual tells you the min rating you can run on the oddy. It's 92 ron. When I ran that I burned my engines up. I drive from just above sea level to 4000' plus. Ever since I ran avgas I have not burned up a single Engine. I even run my machine lean. I run 50/1 oil mix and when you swipe your finger in my exhaust you get NO black on your hand. That's lean. I know for a fact if I put the crap fuel in that you buy for your car its over. Poofkaboom for sure even if I richen it up fat like I had in the beginning. I personally believe the fuel we buy today is not the same stuff they ran in 1985. I can't prove it but I believe it. I have nine piston blow ups to prove it. Here are some. Every man for himself.

Be interesting to see how many people here run race gas in a bone stock 350. I have 3 bone stock. Stock jetting. Only mod is dual intake. I use castor 927 2 stroke oil.

I don't know but all I can say is what my experience has been with these machines. My engines held pressure and vacuum for days (no bull) and they went poofkaboom until I ran good fuel. That's all I can say. I think we are hijacking this thread.

RON and octane are 2 different rating scales. RON is the European rating for gasoline while octane is the rating used in the US. The US octane is derived from RON + MON / 2. So 92 RON (as the FL350 Ody requires) is approximately 88.5 octane minimum.


If your Ody is set up correctly, you don't need race gas. It's a waste of money. Just use 91 (US octane) gasoline and make sure it's jetted correctly.

I run 91 octane with 10% ethanol in it and haven't had an issue yet. I also am running only one of the thin 3 pieces of the head gasket on both of my Ody's.

I have also ran my Ody wide open full throttle for 2 miles without letting up and still had no problem.


Jetting is the key! Just run it a little rich and you can drive it like you stole it!



Rand

I went back with the Original OEM 3 layer gasket that came with the Oddy.

I am going to use the same fuel that I use in my two stroke dirt bikes.

Race fuel mixed with 50 percent high octane gas and synthetic 2 stroke oil at 32 to 1 ratio.

Factory calls for 20 to 1 so I think 32 to 1 should be good.

That mixture seems to work well in my bikes with no problems.

I have not tried to start it yet..just got it back together minus the clutch and put back into the frame.

Sound Good?

Yep, that 20:1 crap doesn't fly anymore!

I have run Sunoco 110 + Pump 93 in a 50/50 mixture with Amsoil Dominator synthetic in all my 2-strokes. I've never had one issue. One of my rigs runs 165-170psi range, so I use the good stuff on everything. Even my 4-poke zero-turn, tiller, pressure washer, and tractor get 93. When you buy it 5gal at a time, the good stuff isn't that must more $. on the other hand, I was paying $8-$9/gal for the 110 last time I bought.

8-9 dollars a gallon is triple what premium costs. I've had zero issues with 92 octane and 32:1 castor 927 oil. Running 3 odysseys and 2 pilots for a week at a time already Costs me $500 in fuel. I could rebuild an Engine a week for the extra cost of race fuel.

32:1 here also.

Were you able to get a compression reading before the rebuild with the 3 layer gasket. If not, and if your compression with the 3 layer is pushing the use of race gas(170lbs+"debatable"), it might not be a bad idea to just run the thinnest gasket (OEM) the thicker gasket portion should be sandwiched between the two thinnest gaskets. When I had my FL350s I remember after installing the 3 layer, my compression was always low(145ish), So i opted to run just one gasket with no problems. Good ol Randy from the late Odyssey Salvage used to build and race the 350's and he would always recommend to use just the thinner gasket if your low on compression. If this is the stock head and cylinder, and head or top of jug hasnt been cut on, this should be a good starting point.

I did not check compression after putting it all back together last night. I could tell by the sound, that it was pretty good. I ran a temp tank just for starting purposes and pressed the start button and it fired up immediately, first try. Smoking and all.
Tonight I am going to figure out the stock fuel tank setup and get that sorted.

Excellent, always good to hear the POP POP of a fresh rebuild