86 SEi Fuel Injector ?

[Rusty Bike]

Hi all, been a while. I have been riding my SEi and always have an annoying problem. Engine stumble as you pull out from a stop. Also bike seems to flood somewhat when you shut it down after extended ride then restart within about an hours time. Besides this the bike runs strong, is reliable and always starts easily. So, with out getting into a discussion of things to check, I would like to know this...How do these fuel injectors work? Are they solenoid operated valves, little pumps like a shot pump? How do they vary the amount of fuel going into the cylinder, do they stay open longer, orifice open up larger? Can injectors leak when not in use, like when engine is shut off? I have Googled early Honda fuel injector operation and find little to no info. So, can someone tell me how these little bastards work or point me to a good source of info...Thanks

[Rednaxs60]

The injectors should not cause the bike to "stumble" when you pull away from a stop. Have you synchronized the throttle valves between the right and left banks. This is recommended every 8,000 miles or so; however, I think once done should be good for at least a years riding. There is a section in the OEM service manual on this.

The injectors on your bike and mine is of the pintle variety. Very agricultural in design. The electrical connection is to energize the internal injector coil that pulls an internal armature up that pulls up on the pintle allowing fuel to enter the intake and cylinder. Here is a schematic of a pintle injector:

Here is a picture of the injector in our bikes without the protective rubber case. The lower green cap protects the pintle:

This picture shows the internal filter screen and where the electrical connector fits:

Injectors can leak after years of use. Crud can build up on the pintle and keep it open a bit. Here is a picture of an older injector and a new injector with spray patterns. Significant difference.

I mentioned to a friend who worked on HDs years back that I was going to clean a set of injectors for my bike. He mentioned that when he did them he would use an ultrasonic cleaner. I have put my injector work on hold for a while as I have good riding weather at the present moment and don't want to take the bike off the road. It is on my work/maintenance list as the next item(s) to be done.

You may also want to look at the air valve that regulates the air into the intake on start-up. This valve takes air from the intake before the throttle plate and directs the air into the intake just before the injector on start-up. It is actuated by the coolant temperature. Here is a picture of the idle air valve:

It is located behind the cover in this picture. Large arrow denotes the location:

Mine starts and runs well, but I do get a smell on start up when cold of excessive fuel. Goes away after a short time, hence my want to clean the injectors. Will also be taking the air valve out and cleaning it as well. Future projects right now.

Hope this helps. Cheers

[Rusty Bike]

Thank you Ernest for the info and the injector diagram. The electric coil opens the pintile to let the fuel pass, i assume then that to increase or decrease the amount of fuel, the time that the pintle is open is changed. As in, more throttle opening requires pintle to open for a longer time. Also, what closes the pintle, I see no spring in the diagram. I have a suspicion that mine are leaking. I feel that after extended operation of the bike that the fuel tank builds up pressure after shutdown due to a hot engine heating a now stationary fuel tank. That fuel system pressure is exaggerating or causing the leak at the pintle causing partial flooding and or very rich mixture at start up. This only happens when bike is shut down for a short period of time. It is definitely starting rich. So far this has not caused hydrolock, thank the Lord! I really do not understand why the gas cap is not vented on these bikes. This rich start senerio never happens if the bike sets over night.

I have not synced the throttle bodies but have purchased a Carb Tune Pro quad set of sticks. I was distracted by the purchases of a 98 Valkyrie Std. As the Valk nears completion I am researching my GW problems. I'll get it all straight eventually.

BTW, how's the parts bike coming? Ride safe brother and thanks again...Rusty

[Rednaxs60]

Glad I could pontificate and possibly shine some light on the issue. I find this gets me to thinking about my bike and the various systems and how each is operating.

The bike in Ontario at my brother's place is getting a vacation until Christmas when I go home for three weeks - family and friends and rides I want to do are getting in the way of progressing this bike this year. I intend to determine if it will start or not at that time, if it starts - trip out here to British Columbia will be in the cards. if not - parts bike it is.

My '85 LTD always starts with a rich smell hence the reason I will do the injectors and work on the fuel system. There is also a reed valve between the air valve and the intake manifold that I will look at. Going to make a parts list for this work and determine what is available. I read about the reed valve and it may require changing, more to investigate.

Cheers

[Rusty Bike]

OK, reread this also.

[Rednaxs60]

Thank you Ernest for the info and the injector diagram. The electric coil opens the pintile to let the fuel pass, i assume then that to increase or decrease the amount of fuel, the time that the pintle is open is changed. As in, more throttle opening requires pintle to open for a longer time. Also, what closes the pintle, I see no spring in the diagram. I have a suspicion that mine are leaking. I feel that after extended operation of the bike that the fuel tank builds up pressure after shutdown due to a hot engine heating a now stationary fuel tank. That fuel system pressure is exaggerating or causing the leak at the pintle causing partial flooding and or very rich mixture at start up. This only happens when bike is shut down for a short period of time. It is definitely starting rich. So far this has not caused hydrolock, thank the Lord! I really do not understand why the gas cap is not vented on these bikes. This rich start senerio never happens if the bike sets over night.

I have not synced the throttle bodies but have purchased a Carb Tune Pro quad set of sticks. I was distracted by the purchases of a 98 Valkyrie Std. As the Valk nears completion I am researching my GW problems. I'll get it all straight eventually.

BTW, how's the parts bike coming? Ride safe brother and thanks again...Rusty

Reread your post. Don't think that there is a change in duration of opening just a change in the number of times it opens each minute. Only need "X" amount of fuel per cylinder firing, so in this regard, fuel is needed faster as the RPM increases but the same amount at each opening of the injector.

I mention this because the FI system on these FI bikes is quite simple and I think a change in duration that an injector is open is beyond the capabilities of this system. A change in the duration that the injector is open would in essence have the bike running lean or rich, whereas I think the aim is to have a consistent balance in the fuel burn at all times.

This is my read on the FI system, could be mistaken.

Cheers

[dbduely]

Hi I have a 85 ltd and love the bike. I had some of the same problem that you mentioned. I cured part of mine with some sea foam. I dose mine with a pretty high dose. What got rid of the stumbling though was syncing the throttle bodies. You probably already know that you don't sync each throttle body, but just from side to side. Good luck

[dbduely]

Sorry one other thing clean the throttle bodies. The butterfly's get gummed up. Don't need to dismantle. Just take off the air cleaner assembly. Start the engine and spray carb cleaner down them. You need to do this before you sync the throttle bodies. Good luck again

[Rusty Bike]

Hi Folks, Merry Christmass. Well, still trying to get my SEi running right but made progress today. I recently replaced my TPS (T0 with a / thur the 0) with the Duncan BEI unit from Mouser electronics. BEI unit was mounted with the help of a custom aluminum adapter slug that Saskarider made. This assembly mounted up nicely after a slight tweek. Set the new TPS and took her for a spin. Eventually I found that the new TPS did not solve my problem. The bike still did the herky jerky thing below 3,000 RPM and has a stumble and pop comming off a stop. That was 6 weeks ago. So, today I installed a new set of plug wires, 7MM solid core from NAPA. I picked up some neopreme 3/8 ID tubeing from Ebay and slid this over the NAPA wires for additional protection similar to the OEM SEi wires. The old plug wires, origional I'll bet, were hard as wood. WAY too old! The roads were clear of salt and ice so I took her for a test ride. 22 Deg out! Well the old girl ran much better, the herky jerky thing appears to be GONE! WooHooo....Much smoother at crusing speed. I still have the hesitation, stumble and pop comming off of a stop but the, below 3,000 RPM issue, seems to be gone. I just hope it stays gone once it warms up again. The stumble problem seems timing related to me?? My coolant temp sensors tests bad as it is 1.6K above spec. when cold. Tests good when engine is hot though. Not real sure about that sensor. I did buy a new one for a 95 Prelude but have not checked it for compatability yet. Looks identicle to ones I found pics of on the web, from the SEi. Well, one step at a time I guess. I do feel I'm makeing progress though. Take care folks.

[Rednaxs60]

Merry Xmas. Trust Santa was good to you and yours.

Found a source of used TPS units for $15.00 over on the Red Pepper Racing Forum - 1985 Honda CRX Si TPS is the same as the one on our bikes. Have two at home now.

These FI bikes are a work in progress for sure. The ECU uses RPM, TPS and PB sensor inputs to determine how the bike operates up to about 3000 RPM. After this it's throttle (TPS) and RPM.

I too had the stumble below 3000 RPM until I opened the throttle enough. My biggest issue at the time was the coils I had installed - non-OEM but new. Put in the old coils and is operating well. Does need new wires and maybe plug caps.

Check your PB sensors, can be weak. Over on the CX500-650 turbo thread is a good read on this: http://cx500forum.com/forum/cx500-cx650 ... ement.html I have installed the Suzuki MAP sensors and the bike is operating well - better manufacturing.

Here are the readings between OEM and the Suzuki. Read in 3 columns.

Inch of Hg/Suzuki/OEM

0/3.45/3.63
5/3.1/3.14
10/2.65/2.59
15/2.18/2
20/1.73/1.43
25/1.26/0.88

Hope this helps.

Cheers

[Rusty Bike]

Yes Ernest, i referenced the CX-T site a while back at your advice. I also sorced the Suzuki MAP's. CX-T site also refered a Toyota MAP that tested nearly indenticle to the OEM. The Toyota item is substantally cheaper and may be a Denso product IIRC. Instead, I purchased SMP AS30 MAP sensors because they are used in an 86 Prelude and they are physicly identicle to the Honda MAP's. These did not work! Unforntunatly, I bought these on Ebay. No way to know if they are any good and I can not send them back so I screwed myself on that move. When I started on my test run yesterday I had a fuel system idiot light on, on the digital dash. I pulled over and lights 3&4 were blinking on the ECU and the W was on steady. I shut the bike off then restarted it. That cleared the codes. Don't know what was up with that. 3,4 blinking is the MAP sensors I think. I think I'm pretty close to getting this bike running right for the first time since I owned it. We got the White Christmass here last night so no more test rideing till the rains wash the salt off again...I believe I'll try n varify the compatability of the coolant temp sensor I picked up. Big problem will be getting to it on the bike. I'll order those Toyota MAP sensors also. Have fun every chance you get!

[Rednaxs60]

Nice to have snow for Xmas, but nice when it goes. When you have a chance, can you post the part number for the Toyota MAP sensor.

The sensor that was indicated is the Gr (camshaft) sensor, the one by your right foot peg on the back of the right cylinder head. These are pretty good, interesting.

The bike I'm working on is my second '85 LTD. It is coming along fine. Have the fuel system light on and it won't go off no matter what I do. More investigation. Think it might be the fuel system pressure.

Took the brake calipers off last night. One pin will not, will not come out no matter what I do. Will keep at it, but thinking another caliper in order. It's the left front. The rotors have been rode hard and put out wet as well.

Everything else is coming along fine. Took the rear off and looked at all the splines, not bad. Did notice one spring missing - the small one in the end of the prop shaft FD side. Not a big issue.

This bike is stock, no add-ons. Interesting look into the past.

Have a good one. Cheers

[Rusty Bike]

Did you try a little heat on the aluminum? A propain torch might free that pin up. You will be replaceing ALL THE RUBBER ANYHOW SO NO HARM THERE. Dam caps lock!
MAP sensor: Toyota-Denso type 100798-5250
order # 89420-02010 Rock Auto
Connector for above DJ7036F-2.2-11/21 maybe Rock Auto or Amazon
I derived this info from the CX500-T site...Good luck

[Rusty Bike]

Note, I errored on the Toyota MAp sensor type number. # should be 100798-5256. Sorry bout that.

[Rusty Bike]

Update: I broke down and bought 2 used Suzuki MAP sensors on Ebay. Suzuki order # 15620-35F00, Type# 100798-5630. (Type # is important) 15 bucks each compaired to 127 each NOS. These are supposed to be a suitable sub for our PBL/PBR sensors. I rigged up 2 harnesses because the correct ones will not be in for a while. Installed the Suzuki MAP's and no joy. Bike had a big dead spot comming off idle so I put the origionals back in. Still had dead spot. ECU showed LEDs # 3 & 4 flashing and 5 on steady. Manual showed either both PB's were bad or TPS was bad. So, I started retraceing my steps. I had set the TPS output (with the shim in the throttle linkage) at .45VDC in an atempt to lean out the fuel mix. So I loosened the TPS and moved it. BINGO, fault cleared and dead spot is GONE! Honda says set TPS at .475-.495 IIRC. I set mine at .460VDC output this time. Still somewhat lean but no trouble code indicated on the ECU. Bike starts instantly and no lag when throttle is bliped! I will not know for sure if I have all problems solved till I get her on the road. Snow here now but it is suppose to be near 60 tomorrow so i may take it around the block to test. Road salt is my main concern. I will reinstall the Suzuki MAP sensors when the correct connectors show up. I will post the results of that for future reference.
So, here's what I have done in a nutshell to cure my preformance issues so far: Removed exhaust and welded new ends on the header pipes where they go into the mufflers. New air cleaner and fuel filter. Installed reman injectors from Rock Auto, Autoline #16313, from 86 Honda Prelude. Installed new plugs NGK, installed Duncan BEI industrial position sensor from Mouser Electronics P/N... 682-9852R5KL2.0. This is a sub for our TO/ sensor and was installed using an aluminum adapter that Saskarider is machineing. Installed new plug wires with 3/8 silicone tube sleves, for extra protection, that were made from silicon tubeing purchased on E bay. Plug wires are solid core from NAPA, Belden # 700172. I checked cleaned and tested just about every sensor and connector on the bike. Electrical testing is easily done at the main ECU connector. You neen the OEM supliment manuals to do this. The BIG FIX was the plug wires and injectors, they made all the difference! So, if shes runnin bad and you have old wires, replace them first. It may save you a LOT of grief. Road test to come..........>>>

[Rednaxs60]

Good for you. $15.00 for a PB sensor is a good price.

Intend to eventually change coils (have found multiple alternatives), wires and new boots. Received the TPS units from 1985 Civic si - $15.00 each USD, as you say better than you can get OEM. Fairly close in size - has the internal connector that is needed without any mod. Will be installing one on the bike at my brother's place before heading across to Victoria.

What connector did you order for the Suzuki MAP sensors?

Have a great test ride.

Cheers

[Rusty Bike]

I ordered DJ7036F-2.2-11/21. Had to order 4 minimum. Couple of bucks! Shiped via a slow boat from China.... You can also use SMP-S-1028 which is 40 bucks! Probably a bunch out there if you search. I did buy the 97 Dodge Neon coil pack SMP-UF403 and had it in my hand. No way that SOB was going to fit in the aloted space without pulling the fairing so I sent it back. As you know, it's pretty tight up there! Pitty actually, it was a nice hefty assembly. BTW, you need 7mm solid core wires, not RF supressor wires. Kinda rare actually. The OEM NGK plug boots have 5K resistors inside them and the OEM NGK plugs are resistor plugs, 5K ohms also. The Dodge coil pack wanted to see a 5K total load so I was going to swap out the cap R's for #6 solid copper wire slugs and just run the right plugs. The tech at NGK was very helpfull! I still don't know if my SEi is fixed yet. Need a road test.

[Rednaxs60]

Thanks for the info. May order a set of those connectors. Can get a set of 5 for $15.00 CDN - still not bad.

My coils come out through the air box, don't have to remove the front fairing. The OEM coils are good, but I'm still convinced that a new set would be beneficial, including new wires. There is a fellow over on the CX 500-650 T forum that has removed the 5K resistors in the plug caps with a straight piece of brass - is apparently working well.

Have looked at Dyna green coils, Accel, Profire, and the Dodge Neon coils as well. Have a source for solid core 7mm wires at the local NAPA store, reasonably priced. OEM coils are still available but at about $150.00 for a set I'm told.

Mentioned to Sonya that I want to bring the '85 LTD across from Ontario. She thought I meant that we would ride my '85 here in Victoria to Ontario return. I mentioned that it was to bring the other bike back, know more about these bikes now then I did two years or so ago. Also talked to my parts guy here in town, mentioned it was started and running well. He mentioned that a mechanic friend of his mentioned that fuel injected bikes are not as problematic as those with carbs after a long lay up. If the bike in Ontario was a carb model, after 3 1/2 years of not being started I'm certain a carb rebuild would have been in order. Cheaper to buy 4 refurbished injectors, and a new fuel filter.

Keeping track of the costs to get the bike on the road in Ontario. There are two '85 LTDs here in BC, the one in Victoria wants $4000.00 CDN, the other in the interior wants $5000.00 firm. My costs are going to be less than these and the maintenance will be done. Learning that the trick with these older bikes especially the fuel injected models is to purchase as inexpensive as possible. The first will be a good learning bike, the second and if you get more will be less expensive to get going and enjoy. Would also space out the work more than I did on the bike here in Victoria.

Cheers

[Rusty Bike]

Yes Ernest, the coil pacs do come out twords the air box. I was to that point but it apeared to me that to install the Dodge coil pack, a bunch of stuff would have to be rearanged. The Dodge item is set up totally diferent. Taking the fairing off would make that rearangement SO much easier. I now feel that my OEM coils are OK, I can find no cracks in them and the bike is running. I'll leave well enough alone for a change...LOL
I do have another bike that fits my build better. This SOB runs!

[Rusty Bike]

My 98 Honda Valkyrie, GL1500c. I bought this before last Xmass with 9,700 miles, paid $2,500.00 USD, in barely running condition. Main problem was, as you said, carbs. I did the belts and a bunch of other stuff and put her on the road last June/July. Tires were 10 yrs old but new! There was hardly any dirt under the fenders! I know, not a Goldwing. It's the crazy step child of the GW. Awesome machine...........>>>

[Rednaxs60]

Nice looking Valkyrie. Always good to have a second bike, especially one that runs. There's no replacement for displacement especially in a lighter frame.

Aren't these bikes fun!

Cheers

[Rusty Bike]

Well, due to a local thaw and against better judgement, I took the SEi for a ride. Did about 40 miles. The bike ran WELL~!~!. Best it's ever ran in my ownership. Stumbel, herky jerky miss, low speed pop, all gone! Cool!
I did have a problem though. Shut the bike off for about 20 minuits and when I restarted it, it stalled. After a couple of tries I realized the fuel pump was not priming the system. So, I banged on that chrome cover several times and heard the pump come up. Stalled again. Banged again, start, stall....... Did that 3 times then is started and was fine. I tried it a few more times, no trouble. Do you have any input on this? Connector or cableing maybe. Pump has always been fine and pretty quiet when running??? Bike is running strong though, red lined it several times but it always did do that with no trouble.
Ernest...I'll send you a pair of these MAP sensor connectors, when I get them, if you want. No charge. They will not be in for a while i guess. Give me you address in a PM. Least I can do. Thanks for the help folks. I'll report back on the Suzuki MAP's when I try them.

[Rednaxs60]

Regarding the fuel pump. Does it come on and shut off with the key on and the bike not started. If so, the next step I would take is to do a fuel pressure test. Had this happen to me on a tour through the interior of BC - two up - going up hill. Bike did not want to go. Let it sit for a bit, same symptoms you are mentioning - start/stop a few times. After about an hour it worked fine and we continued on for another two days arriving home. Have changed out the fuel pump, but do have it on the bike in Ontario and it is working well - go figure. Check the fuel system pressure be my guess first off.

You can also check the fuel pump circuit by following the fuel pump wiring back to the connector just under the seat, behind the turn signal flasher. Should be two connectors there, it should be the inboard one. You can use a test light/multimeter to make sure the circuit is energized when the key is turned to the on position - should shut off after about three/four seconds.

Good luck.

[Rednaxs60]

Going to install new fuel hoses on the bike in Ontario before the trip west. Jimh352 over on the Steve Saunders forum installed an inline filter before the fuel pump on his '85 LTD. This is the one he used: https://www.amazon.com/dp/B000VSDZIK/?tag=goldwingdocs-20 ... -amazon-20

I will be looking for a 1/2" in/out filter as the hoses are 1/2 inch. He has a slightly different fuel line setup - his has the mod for cooling fuel (?). Should be enough room to install a filter before the shut off valve. I want to do this to keep crap out of the fuel pump inlet even thought here is a small inlet filter - easy to be blocked. Might want to have a look at this inlet filter as well.

Cheers

[Rusty Bike]

The pump was not comming on to prime when the key was turned on. When I banged on it, the pump would prime but not run when the engine started. After a couple attempts the engine stayed running. I see there are screw terminals for the pump leads where they hook to the pump. May be a loose connection. I also found while researching last night that the pump motor has a commutator and brushes. May be bad or stuck brushes also. That would make sence with the, bang on it fix! I will pull the cover off the pump later today and see what I see.
When in the USAF, we had a trouble repair code for this type of fix on our wepons control system. Repair code was "FM" which ment "**** Magic"....IOW we banged on a black box and the malfunction cleared and could not be replicated!! That was on the F106. The wepons control system on that bird required 50 hrs of maintance per hour of operation!!
Thank God the GW ain't that bad...LOL
PS, Take a look at the Pingle site for high flow fuel filters. That's what i used on the Valkyrie. Mine is 5/16 in and out. They may have others...