650 Turbo Question

I've got a 1982 650 Turbo that is having some issues. It is all stock as far as I can tell although it may have the "power up" kit installed. The right side exhaust exit is smaller than the left side. A little over 12k miles. Compression is good and I've cleaned and synched the carbs already.

It will start and run and all 4 pipe are getting hot so I believe it's hitting on all 4. It will rev up but not to redline and it is very very sluggish. Also, I do not hear the turbo spin up. The exhaust is coming out of the left pipe and feels like it's got good flow. I thought the turbo might be stuck so I pulled the left muffler and verified that the turbo can be spun by hand. It feels smooth and turns easily. It has some play in the shaft but I understand that is normal?

My question is, if I have the intake path open, like the airfilter box open and the filter out or no boots between the carbs and surge box, should the bike run and rev like a non-tubo 650 or does that make the carbs not work correctly since they expect to be under pressure. It acts like the butterflies are opening but maybe the slides are not rising.

I don't have a manual yet but I will be ordering one today.

Thanks in advance for any help or advice you can offer.

 

Sounds like the fuel pump is not working. Remove the fuel pump and hook up 12volt to it. If it spins then it should work. There is also a cone filter in the fuel pump. Remove it and clean that out. Could also be the fuel pressure regulator. What RPM does it start to die out? Can you get to redline with half throttle? When was the last time you replaced the spark plugs. They only last a few thousand miles before the bike will start to stumble. Besides its a quick and easy fix for only 12 bucks. I would try that before I removed the fuel pump.
Where in the world are you located?

Sean

 

I'll check the fuel pump and screw in a new set of plugs when I get home.

I downloaded a manual and I've been doing some reading so I'm dangerous now! I understand that the reed valve in the surge tank is there to allow the engine to pull air around the turbo if it is not supplying enough so I would make the assumption from there that the engine should run okay with the intake open? For the reeds to open the surge tank would have to be under vacuum, right? So the carbs must be able to work in any condiiton from vacuum to 15lbs of boost?

 

That's correct. The reed valve is there to help with the turbo lag until it spools up. Once the pressure from the compressor is higher than the pressure inside the surge tank, the reed valve closes.

Another common problem is the waste gate - if it's stuck open, the turbo will not build any boost. You can get a 10mm wrench on the actuator linkage... Make sure it moves freely, and snaps closed with considerable force.

 

I have already checked the wastegate and the linkage does move freely and smoothly. If it was stuck open I would have exhaust out of the right muffler, correct? All of the exhaust is exiting the left muffler so I believe it is running throught the turbo.

 

You don't have to remove the fuel pump to see if it runs. Turn the key on, put the bike in first gear and hit the starter. You will be able to hear the pump run. The bike will not lurch as the kickstand switch disables the starter. By the way, have the kick stand down.

You should also be able to hear fuel returning to the tank after a few seconds.

 

The fuel pump does not work. Bikebandit wants $1500 for a new one 8O What are my options? Given that the bike uses a fuel regulator I would think that almost any fuel pump should work? The regulator is supposed to regulate the fuel pressure to surge box pressure +2lbs according to the manual I have. Given that I can run up to 15lbs of boost I need a 12v pump capable of 17lbs of pressure or a bit more to give me some cushion. Please tell me that there is a pump out there that will work :cry:

 

Years ago I subbed an automotive unit for the Yamaha pump. I don't remember the correct fit, but it was for a Chevrolet throttle body set up. The pressure was correct and I was able to bolt it into the stock location, using stock mounts by wrapping it with rubber to make the diameter large enough. It did require some fittings to match the stock fuel lines, but it was a clean installation and worked great. It was available at Advance Auto and Autozone for about $100.00. I hope this helps.

 

It is possible to get the fuel pump unstuck. What you need to do is soak it in solvent or gas overnight. Remove from soak and apply 12 volt power to it. You should make a harness so it simply plugs into fuel pump to power without a spark. After power is applied, tap firmly with rubber hammer around and on each end. When its running put it into the solvent and let it run for an hour or so. I also hooked up the fuel pressure regulator and ran that for a while just to make sure everything was working. I have brought back two fuel pumps this way and the one was working up until the bike met an early demise by having a car run into me. It might take a few days of soaking but it usually comes back. JUST TAKE PRECAUTIONS SINCE YOU WILL BE WORKING WITH FUEL!!!!

Sean

 

I've played around with the pump a bit but have not been able to get it unstuck. It makes one bump sound everytime I switch the leads but has not broken loose yet. I found a 17psi pump online that might work for $50 in the event I cant get this one loose. I'll try soaking it and see what happens and maybe take it apart if I still can't get it loose. I don't really have anything to lose at this point and I found a thread where it looked like someone was able to fix on this way.

 

On another topic.

I was looking over the plumbing and found that the fuel regulator is connected to the manifold vacuum port in front of carb #2 and I know that's not right. I have a tee fitting off of the surge box and it has one side going to the wastegate and the other side going to what I believe is the pressure sensor for the ignition system. It's an electrical component under the air box. I think I need to run that line to the vacuum port and connect the fuel regulator to the surge box but I thought I'd get confirmation on here first?

 

I was able to get the fuel pump unstuck and it does seem to be pumping fuel....thanks dinoracer. The fuel pump relay is bad though os I'll have to replace that. Getting closer though

 

Found a relay on ebay for $10. That's better than the $70 from bikebandit.