Thread: Mercury 200 XRi
03-01-2010, 02:57 PM #1
Mercury 200 XRi
Didn't get a lot of feedback last year, so I will ask again before taking to a dealer.
I have a '92 Mercury 200 XRi on the back of a 21' Ultra LX (family truckster). I bought the boat in March 2008 and have been dealing with this problem from the get go. It seems like it is now occuring more frequently though, so it needs to be addressed.
Idles fine. Drop the hammer and some of the time the boat will not roll over on plane....it will hit about 2,500 rpm and not go any higher. This is with the throttle on the floor. Back down to idle and everything is fine. Try to pop it again and it leaps out of the hole like there was never an issue.
Late last year, a second problem surfaced that I think relates to the first problem. Sometimes after it actually gets on plane, rpm's fall off and then pick back up, then fall off, then pick back up.....sort of like it is cutting in and out as I head down the lake. This is at the typical cruise speed between 3,000 - 3,200 rpm.
Here is what I know:
#1 - intermittent problems suck.
#2 - I don't have a trusted dealer near me, so I would rather have a diagnosis from S&F (trusted source) before I roll the dice with a mechanic I don't know.
My uneducated thought and what was mentioned last year is the Stator. Can the issue be determined with typical diagnostic equipment?
Any guesses or advice would be greatly appreciated.
Last edited by HavasuDreamin'; 03-01-2010 at 06:49 PM.
03-01-2010, 04:14 PM #2
I had the same thing happen to a '92 200 XRI with the same symtoms and I changed the stator, the switchboxes, and as a last resort I checked and adjusted the TPS and that fixed the problem. So I would check the stator and adjust the TPS first.
03-01-2010, 07:19 PM #3
Also check the fuel pump. I mean run it and make sure you are getting clean fuel into and out of the fuel pump. Dad went thru 2 last year. Had 2 brand news die. The last one was spitting rubber and plastic out as soon as it was installed. We had fuel filters on each side of the pump to find where the crap was coming from. Very similar symptoms.
03-01-2010, 07:31 PM #4
I believe the fuel pump is fine. I removed the oil injection last year and subsequently had to drain the gas out to pre-mix and then put back in. I used the electric fuel pump to drain the fuel. The electric fuel pump was pushing clean fuel. The one thing I did notice is that it would run for about 60 seconds and then shut off. Not sure if there mechanism that shuts it off under free flowing conditions or what, but I thought it was strange. My old Holley Blue on my Daytona would free flow for hours.
03-01-2010, 10:24 PM #5
The fuel pump in the VST is only supposed to run for about 45 seconds until the switchboxes fire. That should be right.
03-01-2010, 10:53 PM #6
You have 2 fuel pumps on a XRI, The standard fuel pump on the side of the block that fills the EFI system then you have a EFI electric pump.
The most common problem with this situation is the fuel line & pump bulb between the engine and tank, second is the primary crankcase fuel pump. (not the electric pump)
Stay away from the TPI for now.
This is a sure sign of the basic fuel supply, not associated with the EFI.
Al“The bitterness of poor quality & service remains long after the sweetness of low price is forgotten”
03-02-2010, 06:54 AM #7
Last edited by mrcrsr; 03-02-2010 at 06:56 AM.action mobile marine, 772 528 0754, dealers for aces fuel products,wolf efi, pro marine,latham and gaffrig/livorsi. we build gearcases and modify them(3 litre) to ratchet, and powerheads as well. 21 skater/3 litre wolf efi the engine build http://www.screamandfly.com/showthre...-3-litre-build
03-02-2010, 08:36 AM #8
In this case I say doughtfull. Most electronic problems are pass or fail. Not intermedate with first attempt to a sesessfull second attempt to plaining off.
I say this is the primary fuel system not filling up the vapor tank.
AL“The bitterness of poor quality & service remains long after the sweetness of low price is forgotten”
03-02-2010, 08:44 AM #9action mobile marine, 772 528 0754, dealers for aces fuel products,wolf efi, pro marine,latham and gaffrig/livorsi. we build gearcases and modify them(3 litre) to ratchet, and powerheads as well. 21 skater/3 litre wolf efi the engine build http://www.screamandfly.com/showthre...-3-litre-build
03-02-2010, 09:19 AM #10
As I stated earlier, I had the same vintage motor with identical symtoms. I was throwing money at it buy parts and when I decided that it was the TPS. I had the guy at the shop teach me how to adjust the TPS as he said it was very touchy to set. I paid $100.00 to get it adjusted and taught how to do it and now I check and adjust often. May just be the half dozen motors that I work on reguarly need it, don't know but now I have happy motors and happy boaters. 5 minutes of time can save hours of frustration and a pile of money. I'm not going to say that he does't also have a fuel issue as the surging leads that way. With today's fuel it is always suspect and by all means service it cause a bad fuel system can cost you a motor.
03-02-2010, 01:07 PM #11
I originally thought it was a fuel delivery issue as well. I replaced the in-line filters, bi-passed the tank selector valve and went directly into the water separating fuel filter which was also replaced. I replaced the primer bulb as well to eliminate that as an issue. Under the cowl, I removed the conical shaped filter in the line below the vapor canister. The electric fuel pump works fine as I described earlier. I plan on purchasing a rebuild kit for the second fuel pump to eliminate that as a possibility.
At this point, it could be the fuel pump that supplies the EFI electric pump, but I just don't think that is it.
Does a stator slowy go bad? Like I said, the problem has been occuring more frequently.
Shooter1, what is the TPS? Where is it? What does it do?
Last edited by HavasuDreamin'; 03-02-2010 at 01:14 PM.
03-02-2010, 02:04 PM #12
It is on the bottom of the plenum on the starboard side. It is hooked to the ECU via the wiring harness. It controls the pulses of the injectors as a simple answer. On your particular motor it is set at .250V + or - .010V. If it is less than this value the motor is lean, more is rich on the idle. These tests have to be made with a digital multitester. Stators are usually good or bad. Doing a rebuild on the lift pump is a good preventive maintence with the alchohol in the fuel now. There is a top hat filter near the top of the ECU that can get plugged also but, be careful as it is expensive to replace.
Last edited by shooter1; 03-02-2010 at 02:08 PM.
03-02-2010, 04:16 PM #13
Thanks to all for the advice. This site is great.
Since it is the cheapest, I think I will buy the rebuild kit for the lift pump and at the same time double check the line from the primer bulb to the lift pump (the only part of the line that has not been replaced). If that is not it, at least I eliminated it as a potential problem.
Next, I will have the stator and TPS tested. Can these two items be tested by a local mechanic without placing a load on the engine? In other words, does the boat have to be in the water to test the stator?
03-02-2010, 04:47 PM #14
Both of those tests are done off water.
03-02-2010, 07:32 PM #15
Just my opinion---Save yourself a lot of time and guess work. take it to a dealer who has a diagnostic tank. they're not that expensive to dyno test. they will attach gauges to tell you if its electrical or Fuel. They can also put it under a load to simulate everything you said.