91mazdarx7

i was browsing fc3spro.com and came upon Shimming Eccentric Shaft Thermowax Pellet in stage 1 in this link http://fc3spro.com/TECH/FM2W/power.htm is this something you should do for less of a chance of breaking something ior is it something you dont really need to do how many of you did this any advise is wanted thanks

ddub

If you're doing a rebuild/port you should definitely just do this. If you're worried about it you can do it also, but personally I wouldn't worry about it. It's a bit harder to do if you're leaving the engine in than with it out, just fyi.

Aaron Cake

iTrader: (1)

Basically what he said. Anytime the engine is pulled apart, you should replace the thermal pellet with a solid pellet (available from all rotary shops) or shim the existing one.

91mazdarx7

thanks for the replys my engine only got 60,000 on it and its in my s5 t2 so you's wouldnt worry about it until i rebuild it also should i remove the air pump and acv/egr valve once i get a racing beat dp pre silencer or should i leave it in

Kai

I dropped in a solid pellet in about five minutes with a handy-dandy clutch holder (friend.) It's pretty easy.

I'd say rip out the airpump and all if you don't have to pass any tests. We're mostly anti-emissions around here, unlike some other boards.

RotaryEvolution

iTrader: (30)

you run a risk of dropping the front bearing(which will tear the whole engine to pieces if not caught) when replacing it so i would say no, not unless you do it during an overhaul.

91mazdarx7

i do have emmisions i dont know how ill pass once i get my exhaust finished up so id already be screwed with or without the airpump

RotaryEvolution

iTrader: (30)

keep all your old emissions parts, most people just swap them in/out when it's time to smog.

NZConvertible

Not to pick on Aaron, since this a common attitude here, but IMO this advice is wrong. The thermal bypass pellet is there for a good reason; to get the engine up to temp faster. The reasons for this are pretty obvious and have been discussed many times before, so they don't need to be covered here. The thermal bypass is a component that is known to fail now that these cars are 14-19 years old, and there's absolutely no reason to expect that if you replace it with a new functioning pellet that it won't last just as long again. This is not a failure-prone part, it simply fails when it gets very old. There are no good engineering reasons for not having a functioning thermal bypass valve in your engine. Shimming the old valve or using a solid pellet is just a cheap-*** way of avoiding spending money on a new part.

ddub

This can be avoided by having someone push in the clutch the entire time, though, but yes it is much more risky to do it when the engine is in.

Wankel7

Why is it better for the car to warm up faster NZ? Just off the hip the only reason I could think Mazda would want that is so that the main cat gets to opp temp faster and lowers the cars emmissions?

James

RotaryEvolution

iTrader: (30)

i always thought the front/front bearing was the one that dropped... i haven't had the displeasure of dropping a bearing while removing the front hub so i couldn't say which is more prone to drop down. pushing on the clutch may keep the shaft forward but doesnt mean that oil suction from pulling the hub off won't pull the CAS gear/front balancer forward and allow the front bearing to slip. you could keep either of these from slipping by holding the clutch in and using a screwdriver on the CAS gear to hold it rearward while pulling the hub off, this is what i did when i resealed my front oil galley o-ring.

BlaCkPlaGUE

I think what NZ is trying to say is that the engine needs to warm up in a specific order. If you alter this order by putting the pellet in, certain parts of the engine remain cold while others get hot. Metal expands when its hot, so this could cause some unwanted wear im sure over time.

That is what you were trying to say nz, right?

Syonyk

My opinion: Swap it out.

As near as I've been able to tell, the thermal pellet is one of those "Crap, we have to make this damn thing pass emissions" devices... sort of like the 3k RPM startup.

The thermal pellet restricts oil flow to the rear rotor during cold startup. There's still lots of combustion going on, and the rotor will get plenty hot without oil flowing to it. Strangely enough, these engines almost ALWAYS blow the rear rotor first. I prefer my engine parts oiled.

-=Russ=-

ddub

^^^

I agree, how is it a good idea to restrict oil flow to half the engine basically? Just because Mazda manufactured it doesn't mean it's good. Remember they also manufactured the sub zero start assist that they later said to get rid of.

Wankel7

The question is....did the 787B have one?

RotaryEvolution

iTrader: (30)

i'm pretty sure it restricts oil to both rotors, not just the rear.

Syonyk

That's actually a really good question to ask about various engine things. Near as I can tell, the Mazda engineers had a great, simple, reliable engine... and then the bean counters & emissions people got in the way. Look at how many "goofy things" the engine has for emissions & cost savings (iron endplates, anyone?). I suspect the 787B engine was pure Mazda Engineer Joy.

-=Russ=-

ddub

Pre-1986 rotaries didn't have it.

Sounds like an emissions thing to me!

RotaryEvolution

iTrader: (30)

with how many emissions related components these engines have on them i'm surprised they run at all..

91mazdarx7

so now that there are more opinions on this is it better to get a solid pellet or buy a new thermal pellet

ddub

That's for you to decide. Obviously there are two sides to this argument and each will think they are correct. You just have to decide what you believe or what you think is best.

91mazdarx7

can anyone name advantages and disadvantes for each what is everyones opinion on what one to get

ddub

Solid Pellet Advantanges:

Full flow of oil to engine all the time, not just after it's warmed up. Wont fail.

RotaryEvolution

iTrader: (30)

same here. i shimmed mine, equivalent of using the pellet. most rotary engine builders use the thermal pellet if this helps you decide.