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Old 04-08-2008, 12:29 AM   #1
Ender
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Default Shotgun rebuild

I went to start up my car today a couple hours after parking it, and earlier today I performed a water treatment test and then flogged it a bit on the way to my destination. It ran just fine and pulled hard as usual, however the last couple days it has been stopping once in a while during cranking. I would crank and it would stop then start spinning again, either on its own or sometimes by me letting up on the key then trying again, but promptly start up after doing so. Now I suspect that it wasn't electrical and the motor was instead catching on something. It is currently stuck hard. I couldn't get it unstuck by a roll start, it just lurched hard and might have even dragged the tires (though I wasn't moving fast). I'd say I hope I can roll it forward in reverse and maybe pop it loose by spinning the motor backwards, but I seriously doubt it would run well if I could even start it, if I can pop it loose.

SO, that brings me to the real purpose of this thread: Ender's Shotgun Rebuild. Fortunately, due to my prudence about the realization that the compression was somewhat low, I have already gathered up ALL the necessary parts (and some unnecessary yet delicious parts like the means to street port, a beefier clutch, and the Rotary Aviation OMP adapter). I am pretty much done practicing my porting and I have begun clearancing tonight. This is my first build, but I have done quite a bit of research and I'm finishing up the Mazdatrix DIY rebuild series. I will, of course, post as many pictures as I can manage, time is especially important on this, and if at all possible I would like to have the motor swapped in by Saturday. I do have the whole week off, so to speak. Wish me luck.






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240+ rwhp on my DIY streetport, ~13psi on stock turbo, Racing Beat REVTII exhaust
rTek 2.1 awaits a tune

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Originally Posted by need RX7
This is why I don't do politics, it's just one stupid thing after another.
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Old 04-08-2008, 01:12 PM   #2
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Did you already remove the engine, or are you rebuilding a different core?
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Old 04-08-2008, 01:19 PM   #3
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I'm rebuilding a core.
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240+ rwhp on my DIY streetport, ~13psi on stock turbo, Racing Beat REVTII exhaust
rTek 2.1 awaits a tune

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Originally Posted by need RX7
This is why I don't do politics, it's just one stupid thing after another.
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Old 04-08-2008, 01:35 PM   #4
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I picked up some fittings today after my brief interview, I sure hope I don't screw up any of my plates...
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rTek 2.1 awaits a tune

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Originally Posted by need RX7
This is why I don't do politics, it's just one stupid thing after another.
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Old 04-09-2008, 02:05 PM   #5
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Ah - thats good then, just label everything really well and you should be fine. First times always the hardest, but two, three or four later - you'll be a pro. I can do FB swaps in a day and FCs take about two or three
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Old 04-10-2008, 01:32 AM   #6
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Default Finally I get some work done!

This marks yesterday's and today's progress.

I pulled out my diffusers and realized "Oh, these went through the chemical bath when I had Arnold Motor Supply clean them". The o-rings feel like they would break easily (they are hard, probably brittle), but the diffusers seem ok. Anyone know of suitable replacement o-rings I could pick up at a hardware or parts store? They need to withstand fuel, of course.


Here we have my two practice irons (I really wish I had a center iron to practice on, I'll have to do it another time). I basically followed the Mazdatrix porting video as well as I could, but I don't have quite all the rotary bits needed to do everything they instruct. I think I got pretty freakin' close for what I had. After I was done porting I dug deep to get an idea of where the water jacket is. Apparently a lot of people have tried to cut STRAIGHT DOWN from their port opening and end up with a useless iron. If you ever want to port your 13B, bear in mind that it is NOT beneficial to airflow to cut far straight down anyway. I did not cut straight down at all, and from what I've seen reputable builders also do not cut straight down (I am only talking about the closing edge).


Before I started porting I took at least two hours tapping these two threads... It was annoying, but these brass fittings should last a long time and more importantly, they will be EASY to replace if I ever need to do so. I removed the old nipples because they had some rust and I've had these types of nipples break on me before. It's a huge PITA to fix while the motor is in the car (not to mention hazardous and troublesome to say the least if it happens while driving). I didn't have a drill bit big enough for the big hole, so a lot of time was used cutting it out with the die grinder. I had to do the same for the small hole because my drill chuck isn't big enough for the right sized drill bit. Yippee. At least I got the little one out without cutting the nipple up like I had to with the other one Before I did this I was warned to be careful not to crack the iron around the thread. I was careful and that was another reason it took so long. I'd much rather back it out many times and cut more out periodically than do it fast and have to search for, buy, and then wait for another iron.


I ported the secondaries first, as that was what I practiced on, and they went smoothly. Please note, I did not take pictures of EVERYTHING, as it isn't really necessary and it is time consuming trying to photographically document absolutely everything. The runners were pretty easy, just use your head. They go quickly, too, which was nice.


While I was told that I could use my Racing Beat street port template as-is for all four ports, I decided to shrink it for the primaries.
A) I can't afford (time nor money) to mess them up trying to open them wide up to anything like the secondaries.
B) This does need to be streetable and I like keeping a low profile when it suits me, I suspect I would have to set the idle a bit higher if I made the ports very large.
To accomplish this I simply drew reference marks on the template to show me where the new lines would intersect, marked the intersections on the plate, and scribed the official line by hand.


Since my split mandrel and sandpaper strips won't arrive for about a week I decided to make my own. I would have preferred to shave and cut a bolt for a mandrel, but that would have taken precious time. Also, the best sandpaper I have for the job was 320 grit. 220 is the finest recommended by Mazdatrix, so I went light on its use. The main purpose was to ever so slightly smooth the sharp corners of the inner port openings, I think it did the trick. Good old fashioned ingenuity.


I'm proud of these babies, I think my first primary ports came out well (again though, I don't have all the proper bits so they aren't quite as smooth as would be preferred, but I think I will still receive most of the benefits of this type of port job.


FINALLY, some clear pictures. I think some of the fuzzy pictures are because I was too close and others because I don't have terribly steady hands with something as light as a camera after hours and hours of porting. These are as done as I'm going to be able to get them. I would like some opinions on whether or not these will be safe and reliable for extended use, mainly because I'm nervous about my first build. I was very careful not to nick the faces and not to go past my lines except to very gently blend the sharp points where the template and stock ports didn't meet smoothly. There were one or two very, very minor spots where I went over a line. I remember once was probably .5mm past the outer opening edge line and once was about the same past the closing edge. Should that be ok?
__________________
He isn't a killer. He just wins -- thoroughly.


'87 TII
240+ rwhp on my DIY streetport, ~13psi on stock turbo, Racing Beat REVTII exhaust
rTek 2.1 awaits a tune

Quote:
Originally Posted by need RX7
This is why I don't do politics, it's just one stupid thing after another.
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Old 04-10-2008, 01:33 AM   #7
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Primary runners:


You can compare the two finished secondaries side by side here:
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He isn't a killer. He just wins -- thoroughly.


'87 TII
240+ rwhp on my DIY streetport, ~13psi on stock turbo, Racing Beat REVTII exhaust
rTek 2.1 awaits a tune

Quote:
Originally Posted by need RX7
This is why I don't do politics, it's just one stupid thing after another.
360 gamertag: quick Tii
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Old 04-11-2008, 03:56 AM   #8
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Ported my housings today. Racing Beat street port template, so the closing edge was basically unchanged. I also spent at least 20 minutes getting a crappy plug out of one housing. I had to heat it constantly for ~15 minutes with a propane torch (hottest thing I have available out there) and crank fairly hard on it with a 2' breaker bar. I was none too pleased, because the first surprise was the plug is English. 3/8". Great... So once I got it out I discovered a severely retarded person had installed the plug. The original threads were not only screwed up, the whole plug was inserted crooked. It's like they used an impact wrench from the start and probably didn't even tap a new thread At least I don't think that the turbo coolant passage right there requires a thread, I figure it's just an o-ring and the LIM holds it there. I sure hope that's the case, especially since the other housing's plug (which is in straight) has been (supposedly) messed up by a shop that couldn't get the plug out. I wonder if they fell for the 'try a metric allen socket', because 9mm is TOO SMALL.


One housing prepped for paint, both are cleaned/brushed:


However, I'm debating if I even want to bother painting the motor at this point. I need to get it DONE, ideally I could start the swap Saturday morning. Any thoughts? Suggestions? I won't be able to do much before 10, I have an interview at 10am tomorrow, and I have to go pick up my rotors/stat gears from the machinist. Hopefully they'll be done by noon, and I have to clearance my seals still.

Here are the colors, red for the irons and chrome for the housings if I go ahead with it:


Engine stand w/ 13B head. Had to spend $22 for nuts and bolts just to mount the plate. Stupid Lowe's.


Hey! The stock sound pads are good for something after all! Kneeling mats!
__________________
He isn't a killer. He just wins -- thoroughly.


'87 TII
240+ rwhp on my DIY streetport, ~13psi on stock turbo, Racing Beat REVTII exhaust
rTek 2.1 awaits a tune

Quote:
Originally Posted by need RX7
This is why I don't do politics, it's just one stupid thing after another.
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Old 04-11-2008, 10:41 AM   #9
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Man, I wish you the best of luck. Everything looks super clean and ready to rock.

Get some more pics up of the build when you can.
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Old 04-11-2008, 11:58 AM   #10
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Good luck wit the build everything look greats so far!!
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Old 04-11-2008, 12:05 PM   #11
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Thanks, guys!

Random thought:
My DIY sandpaper flapper worked pretty well on the exhaust ports.

Hopefully I can get the seals clearanced fast enough to get the rotors back to the machinist. He couldn't do the bearings today, but might be able to have them done by tomorrow morning sometime. I really hope so, but once I'm done with that then I can maybe paint, prep the plates for installation, and start pulling the motor before the new one is even built. The more I think about it I do need to check to make sure it isn't just the starter that locked up, if it did and can easily be fixed it will possibly save a lot of trouble involving driving a few hours to borrow my grandpa's car and such.
__________________
He isn't a killer. He just wins -- thoroughly.


'87 TII
240+ rwhp on my DIY streetport, ~13psi on stock turbo, Racing Beat REVTII exhaust
rTek 2.1 awaits a tune

Quote:
Originally Posted by need RX7
This is why I don't do politics, it's just one stupid thing after another.
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Old 04-12-2008, 11:02 AM   #12
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Finished clearancing at about 6 this morning, threw the seals in my super duper seal sorter, then whisked them off to have new bearings installed.


Now, what should I do about this? See that divot in the outer sealing area? I'm sure there's something I can use to seal it, block it off, but I don't know what would work well. I have some assorted glues, JB Weld, body filler and fiberglass; would any of those work well for this?


Wobbly triangles, courtesy of Felix Wankel (sort of...)
http://www.youtube.com/watch?v=SRkXfy7gonk

Now I'm going back out to assemble my engine lift. Hopefully I'll get a call from Car Ex soon marking the successful installation of my rotor and stat gear bearings.
__________________
He isn't a killer. He just wins -- thoroughly.


'87 TII
240+ rwhp on my DIY streetport, ~13psi on stock turbo, Racing Beat REVTII exhaust
rTek 2.1 awaits a tune

Quote:
Originally Posted by need RX7
This is why I don't do politics, it's just one stupid thing after another.
360 gamertag: quick Tii
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Old 04-12-2008, 05:17 PM   #13
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Yar, CarX couldn't change my bearings. I'll try to get pics soon to ask if I really need to change them.
__________________
He isn't a killer. He just wins -- thoroughly.


'87 TII
240+ rwhp on my DIY streetport, ~13psi on stock turbo, Racing Beat REVTII exhaust
rTek 2.1 awaits a tune

Quote:
Originally Posted by need RX7
This is why I don't do politics, it's just one stupid thing after another.
360 gamertag: quick Tii
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Old 04-13-2008, 07:26 AM   #14
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Quote:
Originally Posted by Ender View Post
Now, what should I do about this? See that divot in the outer sealing area? I'm sure there's something I can use to seal it, block it off, but I don't know what would work well. I have some assorted glues, JB Weld, body filler and fiberglass; would any of those work well for this?
Unfortunately, none of those would work well.
A proper fix would be to reweld the aluminum and machine it down to tolerance.
Unforunately, that labor intensive and requires special machinery to do properly (or expensive).

Your rotor housings look like you use some type of sealant on the o-rings?
I don't like to use RTV types of sealant on those o-rings, but it's the only option you've got outside of the more expensive option mentioned above.

Luckily, it's on the outer o-ring, so the stress is not as bad versus the inner o-rings; you don' t have to worry about the inner combustion chambers!


-Ted
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Old 04-13-2008, 07:37 AM   #15
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I looked at them again, and they really weren't in bad shape. Except CarX SCREWED ONE OF THE BEARINGS UP AND DIDN'T TELL ME!! I am furious. It would have been one thing if they had told me it happened, but now I have no choice but to replace all of them and they gave me my parts box back without a word about their condition. I'm calling them today to request they help pay to have the bearings replaced. I would have been able to reuse these without any problems and I was going to do just that until I discovered this.

This is the one, you can't tell well because it's blurry, but it's very obvious on both sides that whatever disc they used slipped.


__________________
He isn't a killer. He just wins -- thoroughly.


'87 TII
240+ rwhp on my DIY streetport, ~13psi on stock turbo, Racing Beat REVTII exhaust
rTek 2.1 awaits a tune

Quote:
Originally Posted by need RX7
This is why I don't do politics, it's just one stupid thing after another.
360 gamertag: quick Tii

Last edited by Ender; 04-13-2008 at 07:45 AM..
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