I'm damned near done taking my engine apart. I just took off the primary injectors, I notice that in the Rotary Aviation video they show little rubber seals around the top of the injector housing, they take these seals out just before they take out the injector diffusers.
I don't have any seals of any sort, it is just metal. What gives with this?

 

The seals sit just inside the very top of the primary injector rail holes where the injectors are inserted. If you do not have any there, then somebody screwed up and you had a boost leak there.

 

Hmmmm....weird. Here is a pic. As you can see, there is no seal at the top. Only the injector diffuser has any sort of seal, I guess I just assumed the injector actually rested on the diffuser. There is a impression on the injector diffuser seal that matches the injector face.
Sorry for the big picture!

 

Can you say fuel leak? Anytime the engine hit boost fuel came out of the gap where the injectors were. That is probably what all that mess is, dried fuel leaves a varnish.

It looks like I see some aluminum rubbings on the center iron. The injector block (or primary fuel rail) should have a little plastic spacer about .080" thick between the center iron and injector block. This prevents heat transfer to the injector block. The factory also used stainless steel bolts to hold the injector block down. Stainless steel doesn't conduct heat as well as steel.

Jeff

 

Wow, that looks like a mess.

If you take a look in the FSM, you'll see the rubber insulators on the primaries and secondaries.

 

Make sure you get new injector atomizers too. They get extremely brittle and break. The pieces can fall into the motor and cause damage.

 

Jeff: The insulator was in place okay. I agree with you about the fuel varnish....I am amazed my engine performed as good as it did.

Mahjik: Thanks for the reference to the FSM page, I will go check it out.

Rotary Experiment Seven: The 'atomizer' is the diffuser I have in my hand, correct? The Rotary Aviation video says these are "very expensive".....I wonder HOW expensive.

Also, while we have the pic up....do you leave the little brass orifices in the oil injector holes? They have a slot in them but I gently tried to turn one with no results.



Thanks, guys!

 

i have had no problems reusing the atomizers. *shrug*

 

They are not that expensive (air bleed sockets as referred on that page of the FSM I posted). You can get them in the fuel recall kit I spoke about in your other thread.

I would recondition the whole fuel system. IMO, it doesn't make much sense to put in a good motor with bad (or possibly bad) components, especially the fuel system components.

 

^ most definitely agree! ^
I plan on making this engine be just like new, or actually better.
I am going to make sure the injectors are flowing/spraying good (though I don't have a clue where to send them to), get a new fuel pulsation dampener...the whole nine yards.
I still find it amazing that this engine didn't have the little seals in there!

 

Wow, I'm surprised you didnt have some major issues. The air bleed sockets are expensive for what they are but If i remember correctly between $18-25. www.rceng.com/Default.htm is a place many have sent their injectors to in order to get them checked out. There are some cheaper places but none come to mind currently.

 

I just sent mine off to witchunter. They charge $15.00 each for cleaning and flow test. Well worth the money.

 

Agreed, and 15 bucks each isnt anything compaired to just about anything having to do with an rx7...

 

Thanks again, guys. Can someone shoot me an address for Witchunter, please? Or a contact?

Thanks!

 

http://www.witchhunter.com/

However, I still recommend RC Engineering: http://www.rceng.com/ even if they are a little more expensive. I had mine done by them at the beginning of this year.

 

Thanks, Mahjik!

Hey, do I have to take the studs out of the front of the engine where the water pump goes as well as the pan to prepare it for most rebuilders? I took the oil level sensor out of the pan already, but wasn't sure about the pan itself nor the front studs.

 

I don't think it matters about the front cover WP studs. They would probably prefer to have them gone though (unless they are assembling the water pump and WP housing for you).

As for the oil pan, talk to whoever is going to rebuild the engine. They may seal up the pan for you.

 

Wow I already got mine back today. Here are the numbers:

Spray pattern:
Before ---- Good / Good / Good / Poor
After ------ Good / Good / Good / Good

Static Flow
Before ----- 113 / 112 / 109 / 105.5
After ------- 114 / 115 / 114.5 / 115

Pulsed Flow
Before ----- 120 / 118 / 112 / 106
After ------- 122.5 / 122 / 121.5 / 122.5

Oh yea these are off my 91 S5 vert that recently blew the rear rotor. I'm not an expert on the numbers. Were my before numbers really bad anyone? The last two numbers were of the rear rotor injectors. Anyone think the lower flow was enough to blow an apex seal on a NA rotary?

 

bajaman when you send off the injectors, they will also replace the upper o-rings and the lower rubber seals. That I didn't expect.