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Old 07-29-2008, 01:12 AM   #16
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I don't think you can go by the 00 numbers because they are putting updated carbs(21J) on all the new ones made in 08 and the one i just bought has the newest carb and its only an 002 on the box. So its pretty safe to say if your engine came with the updated carb it should have been built recently.
I think so too. But What I know is starting 002 they have changed the rear bearing to 9 balls from 8.

Whats the difference of the new carb with the old one? Did they address the Idle Screw Problem? Well Actually only my problem. I find it to hard to adjust the idle screw when you already have the engine installed in the car. It hard to reach it by a flat head cuase it is seated underneath the carb and the pipe is on its way.
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Old 07-31-2008, 03:28 PM   #17
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My buddy's V-Spec started backfiring, flaming out and running very poorly the other day. I checked his flywheel and felt the same "dead spot" I have on mine and thought he was screwed. Another guy at the track checked his V-Spec and had the same thing and his was running great. So, that's not a problem.

My buddy checked his glow plug and it was nasty. A new one resulted in a strong running engine. Easy solution.

The glow plug solution didn't work for me but I'm not thinking that maybe my new bearings might have done the trick. I'm going to throw it back together and put her in the buggy and see if I'm in business. Thanks for all the feedback guys. I'm sure you'll be on the edges of your seats waiting to see if it's working again so I'll be sure to let you know.
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Old 08-14-2008, 06:24 AM   #18
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Originally Posted by oggietiu View Post
I think so too. But What I know is starting 002 they have changed the rear bearing to 9 balls from 8.

Whats the difference of the new carb with the old one? Did they address the Idle Screw Problem? Well Actually only my problem. I find it to hard to adjust the idle screw when you already have the engine installed in the car. It hard to reach it by a flat head cuase it is seated underneath the carb and the pipe is on its way.

Now i know thanks oggietiu
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Old 08-16-2008, 09:12 AM   #19
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My RBws7III had the same dead spot when it was brand new. Its normal. Most good engines I've felt have it. Some even make a clicking noise while turning past this spot.

It isn't easy to see on the OS stuff because of that monster pinch they have when new.

Near top dead center the piston moves a little less at a certain spot per degree of crank rotation. It feels easier to turn at that spot. (Within reason of course.) The leverage the piston has on the crank changes during its rotation.

I've been told to clean the motor. Take off the back plate and heat the crank and conrod with a heat gun. If there is side to side play in the conrod/crankpin area then replace the conrod. Usually the play is noticable when its cold but It seemed reasonable to see what happens when its warm as well.

Usually the conrod bushng wears much faster than the crank. I'll replace piston/sleeve/conrod. But the only time I'd invest in a crank is if the rest of the motor is in real good shape. If I need the crank and piston etc., I'll just buy a new engine and keep the other as spare parts.
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Old 08-17-2008, 12:39 AM   #20
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This weekend I tore apart the "old" V-Spec with the intention of replacing the front and rear bearings and the crank arm. After checking to make sure the piston and sleeve still had decent pinch I got to work. Getting the rear engine bearing out was a challenge to say the least. I had to cook the crank case in the oven for 30 minutes on 350 and it was still tight! I got the two new bearings in correctly, lubricated them and then installed the new crank arm. When I got everything back into the crank case and rolled the engine over TDC I still had the same dead spot...damn!

Now I'm at the point where I've spent enough I'm determined to just fix it (which I realize may never happen). What is the next logical part to replace? Should it be the pin at the piston head (wrist pin?) or could I be looking at needing a new crankshaft. I assume the crankshaft pin can not be replaced independently of the crankshaft. What would you guys do?
The dead spot is normal. Its called Dwell. The time the piston is spent at tdc.
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