1999 21v Riders Edition issues

[COTige21V]

Well the time to break out the boat for the season has come.

I dewinterized the boat which included new plug wires, new spark plugs and putting all plugs in running the boat for a few minutes. Ran amazing.

I took out the boat shortly after dewinterizing. Started up, engine runs good but when i get on the throttle it wont plane. It won't go above 12mph and no wakeboarding or surfing till this is fixed. Sucked because my son was in town from the Air Force.

I have read that it could be fuel starvation, knock sensor or something with the transmission. From what i read here is the only things I have checked and what I am going to chek this weekend, it is going to be cold here in Colorado so cant take it out anyway.

Things checked
- Transmission fluid is full and good color (no water)
- V-Drive oil is low about half between low and high.
- throttles fine in neutral but under load, shudders and stays under 12mph about 2500rpm.
- I did put fuel stabilizer in it for winterization but didn't run it to circulate it which could have clogged the fuel filter.
- one mistake I made while running the engine during dewinterization. When I started it to run I had to throttle and it was left in drive (not neutral) and spun the prop very quickly for 1 second max 2 seconds. Only thing i saw was the most minimal bend in a blade on the prop. It was not bad at all.

Things I am going to check this weekend. Fuel pressure, fuel filter (is the only one this boat has the water separator filter?), all wiring connections to the knock sensors and the SW switch too. Check coil and ignition current and resistance.

Anything else I should look out for? Has anyone else had this happen?

As always. You are the best group of people out there for Tige owners. So I humbly appreciate you.

[Zzzzz5]

Well the time to break out the boat for the season has come.

I dewinterized the boat which included new plug wires, new spark plugs and putting all plugs in running the boat for a few minutes. Ran amazing.

I took out the boat shortly after dewinterizing. Started up, engine runs good but when i get on the throttle it wont plane. It won't go above 12mph and no wakeboarding or surfing till this is fixed. Sucked because my son was in town from the Air Force.

I have read that it could be fuel starvation, knock sensor or something with the transmission. From what i read here is the only things I have checked and what I am going to chek this weekend, it is going to be cold here in Colorado so cant take it out anyway.

Things checked
- Transmission fluid is full and good color (no water)
- V-Drive oil is low about half between low and high.
- throttles fine in neutral but under load, shudders and stays under 12mph about 2500rpm.
- I did put fuel stabilizer in it for winterization but didn't run it to circulate it which could have clogged the fuel filter.
- one mistake I made while running the engine during dewinterization. When I started it to run I had to throttle and it was left in drive (not neutral) and spun the prop very quickly for 1 second max 2 seconds. Only thing i saw was the most minimal bend in a blade on the prop. It was not bad at all.

Things I am going to check this weekend. Fuel pressure, fuel filter (is the only one this boat has the water separator filter?), all wiring connections to the knock sensors and the SW switch too. Check coil and ignition current and resistance.

Anything else I should look out for? Has anyone else had this happen?

As always. You are the best group of people out there for Tige owners. So I humbly appreciate you.

If you have the Mercruiser 350 Mag it should have an inline fuel abs a separate fuel filter/water separator. You can look up exact parts diagrams/numbers here:

http://www.marinepartsplus.com/catal...PI_ALPHA-BRAVO

I had an issue with the IAC preventing my boat from going over 3000 rpm’s. It started and ran fine then just hit a wall and wouldn’t rev any higher, regardless of any other factors.

https://www.amazon.com/gp/aw/d/B0794...b_b_asin_title


Sent from my iPhone using Tapatalk

[COTige21V]

Zzzzz5, thank you. I will look into both fuel filter and separator. I am just trying to research. Was hoping to work on it this weekend but Colorados bipolar weather had other plans lol. But I will replace the filters and the IAC. It can't hurt and is not expensive. Thank you again.

[COTige21V]

If you have the Mercruiser 350 Mag it should have an inline fuel abs a separate fuel filter/water separator. You can look up exact parts diagrams/numbers here:

http://www.marinepartsplus.com/catal...PI_ALPHA-BRAVO

I had an issue with the IAC preventing my boat from going over 3000 rpm’s. It started and ran fine then just hit a wall and wouldn’t rev any higher, regardless of any other factors.

https://www.amazon.com/gp/aw/d/B0794...b_b_asin_title


Sent from my iPhone using Tapatalk

I replaced the Fuel Filter/water seperator and the IAC.. Ran decently for the first little bit under no load (wakeboarding and surfing). Then we decided we would try and under load it cutout like it was starving fuel.

Got the boat back and took a look at fuel pressure. Pressure would build just fine but fall off. So I took off the vacuum to the FPR and it didnt change. So I changed out the fuel pressure regulator and fuel pump (While I was there). I alos noticed two cracked plugs on two of the injectors so I just said F it and ordered all 8. I replaced those as well and Now pressure wont even build. I have to key prime it about 4 times to get pressure up and it will hold but as soon as I start it it will die and pressure does not maintain.

[COTige21V]

One other thing I noticed was my coil wire was not good. I will replace that but I dont think that has anything to do with the fuel pressure.

[boatwakes]

Shuddering indicates either the engine is not firing on all cylinders, the plug wires are not connected in the correct order or the bend in the prop blade is way worse than you think. Check all the plug wire connections first (I don't recommend doing this with the engine running, shock hazard) and verify they are in correct firing order which is clockwise 1-8-4-3-6-5-7-2 as you look down on the distributor cap. On that engine (V-drive GM small block) the number 1 cylinder is starboard side boat aft and number 8 is port side boat forward. I've seen firing order issues when wires are replaced so I'd start there.

If they're all good, look to the injectors next. Prior to performing this test, become familiar with how to remove the wired injector connection at each injector plug, you-tube videos abound on this subject but its fairly simple, pinch the small wire that covers the front of the injector connection. This will release the holding clip and then wiggle the connector off the injector. A word of caution, be careful with how much wiggle is applied, I've had customers break the neck on the injector when trying to remove the connection.

Next, with the engine running in neutral, raise the rpms to approximately 1500 and one at a time, remove the injector electrical connection at the fuel rail and note if the engine rpm dips. Reconnect after each one and if you find one where the rpm does not change, thats your culprit cylinder. At this point you'll need to determine if its the spark plug or the injector thats not firing. If you immediately remove the spark plug after finding the dead cylinder and find it covered in fuel, the plug is the problem. If you remove the plug and its dry, its the injector. To verify, swap the plug from the dead cylinder to another known good cylinder and retest.

Please repost your findings.

[COTige21V]

Thank you BoatWakes.
I have new injectors, fuel pump and fuel regulator. Pressure was an issue now it is back to spec.
It runs like garbage though so I am either going to go with a HEI distributor with coil built in or just start there. Fire order is fine, wires, spark plugs, rotor and cap are new.
changed out the IAC as well and just running very sluggish. Almost like a missfire.
Does the injector wiring order matter? I think i got them the way theybare supposed to go but couldnt find anything online about how they go? I have two sets of green and blue wired plugs going to each bank. 8 total 4 blue and 4 green.
None the less, I am going to continue trying things before I result to putting more parts to it. Double check the firing order and clean any electrical connectors.

Any advice is appreciated.

[COTige21V]

Had a Boat mechanic take a look and fuel pressure is good, injectors seem to be good he said he doesn't know the exact wiring color but we unplugged and plugged them in again till it sounded good. Put a spark plug wire check and found 2 and 3 are not firing, changed the wires, still not firing. I have my new ignition sensor with the 3 wire coming tomorrow and even my new plugs were fouled pretty bad.
does anyone have a picture of the 350 mag mpi injector harness and where the blue and green wire plugs go? Tomorrow I am changing wires, plugs and ignition sensor. We also changed the TPS as his scan tool said it had high and low voltage on the TPS. I have not changed out the IAC but have one. Essentially it starts, idles and dies. Fuel pressure is 32 on power and about 40 while it runs.

[COTige21V]

I might be able to get you a pic tomorrow if you don't get an answer.

That would be awesome Gumby thank you

[COTige21V]

Awesome thank you Gumby. Thay helps me a lot. Got the new plugs, wires and 3 wire ignition sensor in. Now just need to set timing and hoping all is good.

[COTige21V]

I did not know that. But this is really good to know. I am having the mechanic do it as he has the computer and timing gun. Not sure on the process with this engine.

[COTige21V]

Mechanic couldn't get it running good. 2 and 3 cylinders are not firing even after changing ignition module, cap, rotor, wires and plugs. I just want to upgrade to an aftermarket distributor that has coil built in and doesn't need to be timed.
Ughhh.
boatless for our annual camping boating trip. I just want to LS swap it lol

[COTige21V]

COTige21V ...So in the end you have done a new fuel pump, Injectors, TPS ,IAC.Pickup in the distributor, plugs,( AC Delco) wires, cap, rotor, is that al of it? have you done a compression check on the 2 and 3? something is just not adding up.what dose the spark Look like on those two? do you have a spark tester?

You got it sir. Almost acts like it is still starving fuel but don't know because 2-3 do not fire. With all the changes to the distributor, have you ever seen this? I am about to upgrade to an HEI digital ignition some company named A-team has that you don't have to time. It will automatically time it and works great. At least that's what the company told me lol

[COTige21V]

Ohh and yes spark tester showed no fire for 2 and 3. I am going to do the compression test tomorrow.

[COTige21V]

Well that compression test took forever. Lol.
#1 - 140
#2 - 135
#3 - 140
#4 - 60
#5 - 140
#6 - 60
#7 - 140
#8 - 140

with 4 and 6 being low I am thinking head gasket. It is raining right now and I will do a wet compression on those two cylinders and report back once I can.
is it okay to use fogging oil for a wet test?