'85 LTD Engine Missing and Stopping

[frankroche]

So according to electricity theory, current floes around the outside of the wire, so a many stranded wire of 12 gauge should flow more current than a single 12 gauge wire.

For what it's worth

 

[Rednaxs60]

frankroche » Yesterday, 7:11 pm[/url]":8yzqnpxa]
So according to electricity theory, current floes around the outside of the wire, so a many stranded wire of 12 gauge should flow more current than a single 12 gauge wire.

For what it's worth

Frank - no worries. Befuddling the hell out of me. I know there are aspects of a system that a change in a part from the original is not always good, but would like to understand the why. Will be reaching out to other forums as well. Maybe the racing community can shed some light on this topic.

Cheers

 

[joedrum]

Depending on what plugs you use and the spark produce at the beginning of things ...makes a lot of difference on the wire that is used to flow things in the middle of it all ...I think best way to look at it is matching parts ...one non matching part can screw things up ...is my opinion ...how do you know they match ...it runs well and last ...and nothing gets over heated

 

[Rednaxs60]

Always something. Clear up one issue, if it was the issue, and another will show up.

Bike is testing my resolve. Replaced the fuel pump with a newer one I had from last year. The older style, identical to the OEM original, was making noises I did not like. Will be making a special inlet elbow to take out the hose bend. can always improve on the design a bit.

Bike worked well then decided to quit. Noticed that the alternator light was out when the key was turned on. Alternator gets field power from the auxiliary fuse block through a relay. Waited a few minutes, turned on the key, alt light came on, engine started. The power to the coils also comes from the auxiliary fuse block directly, better power supply to the coils. No error codes on the ECU.

Got the old girl back in the garage, replaced the relay, went for a 150 Km ride with a friend for coffee. Bike operated well.

Next morning went to go out and the engine started to miss. Turned around straight away and back to the garage. Now I have a TPS error code. Okay, older TPS, nothing lasts forever.

Checked the plugs as well. Did some research and dry soot on the plugs is indicative of a fuel issue. Have dry soot build up on the right side plugs. Replaced the plugs.

Replaced the TPS and got rid of the error code. Went to balance the right and left cylinder banks and only the left bank draws a vacuum of any sort. The right side does not do anything. Checked the cylinder pressure on both sides and down around 75-90 PSI. Last time I checked it was 125 PSI. I'm hating the worst in that a valve job is going to be required. Not going into the engine because it does not burn oil so the rings should be good.

Having no vacuum on the right bank also affects the PB sensor on that side, and could also be the reason the TPS error code is in play. Reading the supplement and looking at the description of TPS error code leads me to this conclusion.

To confirm everything this morning, went out and took the TPS units I have and bench tested them. Two out of three were within spec and worked correctly. Checked the wiring from the TPS back to the ECU plug and all is well.

Checked the ohm readings for the Ns and Gr/Gl sensors as well. Within spec.

Time to order a couple of head gaskets and some lapping compound. Been a long time since I have taken an engine apart, let alone a motorcycle engine.

Also looking at my schedule and 1 May is fast approaching. Don't want to take things apart and then leave for 6 weeks.

If anyone has some ideas, all accepted. Cheers

 

[Rednaxs60]

Been perusing the parts fiche. Should be able to lap the valves, install new valve stem seals, and head gaskets. Did this on a '68 Mustang back in '75. Drove it for another 10 years with only this work done. Been following a fellow over on NGW forum who did this work as well.

Time to order parts.

 

[Ohara]

Good luck Ernest :good: Once you get started it will be interesting...

 

[Rednaxs60]

Another day and a good sleep can make a huge difference. Came up with a game plan for this morning.

Decided to prove the TPS wiring. Confirmed that the wiring was correct and supplying 5 VDC to the TPS and that the TPS was operating as it should. Next I hooked up my make shift power supply ( 3 AA batteries) and made sure I had a voltage signal to the ECU connector. All went as expected.

Next I put the TPS in and calibrated it according to the OEM supplement. Got the 0.475 VDC on the TPS with my make shift filed nut to get the 0.110 spec spacer between the throttle stop and linkage, hooked everything back up. The TPS code went away - think I had it calibrated wrong.

I also hooked the right PB sensor in parallel with the left PB sensor and hooked a vacuum gauge into the right vacuum lines because I could not get a draw on the right side with the manometer.

Started the engine and it operated terribly, but I had also backed the throttle linkage off as well.

Put the alternator back on and connected into the system - can only operate the engine and bike systems on the battery for so long.

Stared the engine and commenced balancing the right and left cylinder banks with my heat gun. I did not expect the manometer to work that well so I went a different route. Used 1/4 turn increments to get the cylinders balanced. Once I got close I started using 1/8 turn increments, then to very small less than 1/16 turns - more like a little bump.

After each incremental change, let it steady out then took a heat reading. Using this adjusted the RPM and balance screws to adjust the heat signature on each side. Takes a bit more time, but this procedure does work and takes me back to the good times I had in my Dad's garage in the '60s.

Letting the engine cool down for a bit then I will reset if required the TPS voltage, and check the cylinder temps again.

I'm just happy that there are no error codes on the ECU - for now.

More to follow, and thanks to those who have read my rant, good to think these issues through.

Cheers

 

[Rednaxs60]

Did the last calibration of the TPS. Reset it to 0.472 VDC, close enough to the 0.475 VDC output with the shim under the throttle linkage, it is not a high end system, but it does have its quirks.

One other aspect I am paying attention to is the wiring and protecting it. Gerry did some wiring harness work and used the TESA anti-abrasion tape instead of the vinyl. Picked up a few rolls and do believe it will be quite beneficial. Costs a bit more but the benefit is that it is very flexible unlike the standard vinyl type tape. Going to be my go to for a while.

Have the bike back together, idle set, and no error codes. Have to wait until tomorrow for the road test, but it will be what it will be. Just glad it's back together again.

Cheers

 

[Rednaxs60]

Kept at the issues. Have finally come to grips with everything.

Plug wires and new boots are good. TPS adjusted to 0.475 VDC. Adjusted it quite a bit because of balance/RPM adjustment. Any time you adjust the balance/RPM you should adjust the TPS to suit. It does make a difference with the exhaust smell.

I changed out the old OEM style fuel pump from a VW I think. Put in the Spectra SP1186, it's also a bit long as well but has the proper end to match the supply hose to the fuel system. I did change check the fuel hoses and the lines are all clear. From the shut off valve to the fuel pump I put in two 90 deg elbows. The elbows I could find to do this were PEX 90 deg brass elbows that are used in water systems. I shortened the fuel pump inlet barb and one of the PEX 90 elbows to fit. Used Green Line fuel hose, doesn't bend very well, looking for another alternative.

Found some new oil to try, European formula full synthetic 5W40, no friction additives. Seems friction additives are a North American requirement. $6.50 CDN a quart, can get it to $5.50 CDN a quart if I want to buy it in case lots. Went for a good ride today and no clutch slippage so all is well. Purchased this at Bumper to Bumper here in Victoria, there are stores across Canada. Will be buying some for the bike in Ontario. Costs less than standard mineral motor oil. I check the API donut for the spec. It is an API SN standard oil and the bottom half of the donut is blank, no specific additives or friction modifiers. Have to remember that my bike is 1985, JASO didn't come out until 1999, and my bike was designed to use oil based on an automotive spec.

Did have some electrical wiring connection issues, tightened these.

Put the alt that I had purchased last fall for the LA trip back on. The one that was on was a $30.00 special from a wrecker. Took it apart and quite rusty all through, won't be putting it back on.

151 Km (just shy of 100 miles) road stress test today and all is well.

I think I've got it figures out.

These are wonderful bikes if you don't weaken.

 

[Rednaxs60]

Took the old girl, and went for a ride up the coast to Port Renfrew for a burger. Went two up, had the better half with me. Nice ride for half the journey and then it went overcast and cooled down quite a bit. Bike operated well.

Nice scenery. Stopped at Jorden River where the fellows were out kite boarding:

Stopped at The 17 mile house for coffee and coconut cream pie:

Now for the interesting part. On the way back, the engine RPM would start to drop. No missing or anything, just start to fall off. Apply a bit of throttle and can idle no problems. The engine temp would go up to 6 bars when riding start/stop in the city but the fan was not on, should not be an issue. Engine temp dropped back to 4 bars when up to speed on the roads. Any RPM over 1000 and have 14.3 VDC on the gauge.

Wondering if engine temp and low engine compression has any relationship. Got back to the garage, let it cool down for about an hour, started right up and idled just fine. Will monitor and think about it - research the net as well. It will be sitting for a while as I now will be turning my efforts to the final packing for the trip east to get the other bike.

Cheers