Was near the end of my usual leisure Sunday ride when the FJ started running a little rough. Since I was so low on gas that the fuel light came on when going up hills I figured the bottom of the gas tank may be a little contaminated or has a little water in it (it's happened before). So I emptied the remaining gas from the tank, went to the gas station and got a couple gallons, put that in and tried to start it up. This bike always starts instantly but this time after a lot of cranking - nothing. Then suddenly it backfired so loudly that a neighbor came over from across the street to see if I was OK. It sounded like a gun going off. Anyway, I took off the tank and pod filters to see if there was any damage to the carbs but no visible problems. Put the bike in the garage and gave up. So the question is: Did this do any damage to the engine? Is it an indication that something more serious is wrong? Or should I just put the tank back on and try again tomorrow?
I would try it again today (after the Raider game). Dont know for sure why that happened but if all was normal before, for now I would chalk it off to an unusaul condition of empty fuel system or maybe it was flooded.
I doubt you did any damage to the engine as backfires happen outside of the engine. If the pods were ok then the backfire was out the tail pipe. If you have not had this issue before then I would not stress over it. If it happens again then post up with more information on what happened. Draining the tank may have allowed some water into the carbs. This may have allowed a rich fuel situation to build up resulting in the backfire. I would drain all 4 carbs to make sure any water is also drained out. Check the fuel that drains out to see if water is sitting on the bottom of the collection cup.
Thanks for the advice! Nice to know it shouldn't have done any damage. I'm going to buy some new spark plugs tomorrow before putting the tank back on - about time anyway. Will also try draining fuel from the carbs and checking for contamination. Then try starting it up again. Will update this afterward. Oh, and how bout them Raiders.
Raider are real contenders again. feels good, dont count them out this year. Another come from behind win today! :yahoo: Oh and yeah good to have tamper proof screwdriver set.
Drained the carbs and checked for contamination. Went to the auto parts store and bought a new vacuum hose for the fuel petcock because the old one looked a little weak. Put a safety wire around the petcock fuel outlet as has been mentioned on another post. Put more oil on the air pods because they looked a little dry. Then realized I had reversed both sides of the spark plug wires while taking out and cleaning the plugs!!! #2 wire running to #1 cylinder, #1 wire running to #2 cylinder, #3 running to #4 cylinder, etc. Put it all back together and it started right up - ran fine - so there was no damage done. To quote another great Alabamian, "Stupid is as stupid does."
Awesome, happy to hear you found the issue and she runs well again.
Good for you!
As a side note, you if you have foam UniPods, don't oil them, oil is no good on foam, use foam filter spray.
If you have the pleated paper filters (K&N) throw those away and get the foam UniPods.
The fuel vapor from the carbs wash the oil off the paper filters and thus you lose filtering ability.
Oh, thanks for that. I'll have to order the right stuff from RPM. I replaced my old K&N filter pods with the RPM duel pod filters but have some K&N oil so used that. They appeared to be completely clean of the oil after just 500 miles or so. Life is like a box of chocolates, you never know what you're going to get.
Quote from: Pat Conlon on December 05, 2016, 08:45:45 PM
Good for you!
As a side note, you if you have foam UniPods, don't oil them, oil is no good on foam, use foam filter spray.
If you have the pleated paper filters (K&N) throw those away and get the foam UniPods.
The fuel vapor from the carbs wash the oil off the paper filters and thus you lose filtering ability.
A hijack: do I need to oil HiFlo paper filter? It wasn't mentioned anywhere on it, it is stated as OEM direct replacement. Was original paper filter oiled?
PS: Ah, I found what I wanted to know. Apparently air filters are not oiled, only foam ones as K&N states.
Quote from: Pat Conlon on December 05, 2016, 08:45:45 PM
Good for you!
As a side note, you if you have foam UniPods, don't oil them, oil is no good on foam, use foam filter spray.
OK, so what's in the can? I always thought it was just filter oil in a spray can for easier application.
Noel
Quote from: ribbert on December 06, 2016, 04:17:13 AM
OK, so what's in the can? I always thought it was just filter oil in a spray can for easier application.
Noel
I think what Pat was saying is that oil like motor oil is not what should be used. The UNI oil gets real sticky and traps the dirt better.
Correct. Oil for paper filters. Foam filter spray for foam filters. You can use UNI or PJ1, etc, most motorcycle shops carry foam filter spray.
Very popular for dirt bikes.
UNI Part Number: UFF-100, Description: 5.5 oz. aero - Oil
(http://fjowners.com/gallery/10/1388_06_12_16_12_25_22.jpeg)
Yes Marty, paper oil vs foam oil, they are both oils, but for different applications.
I don't remember ever using oil on paper filters. They were always dry. They tend to flow quite well but at the cost of not filtering well.
Pat,
Do you mean cotton gauze filters like K&N?
Some paper filters need no oil and should remain dry, some paper filters are designed for and need oil , like K&N.
Quote from: FJ_Hooligan on December 06, 2016, 08:17:09 PM
Do you mean cotton gauze filters like K&N?
Exactly.
"The K&N air filter is somewhat more complex. The unique design features multiple layers of oiled cotton fabric"
K&N's Air Filter Facts (http://www.knfilters.com/filter_facts.htm)
Funny how this thread has morphed into air filtration after being being started for "Loud backfire" :rofl2:
Quote from: FJ1100mjk on December 07, 2016, 04:39:49 AM
Quote from: FJ_Hooligan on December 06, 2016, 08:17:09 PM
Do you mean cotton gauze filters like K&N?
Exactly.
"The K&N air filter is somewhat more complex. The unique design features multiple layers of oiled cotton fabric"
K&N's Air Filter Facts (http://www.knfilters.com/filter_facts.htm)
Funny how this thread has morphed into air filtration after being being started for "Loud backfire" :rofl2:
Evolution at work. :wacko2:
Quote from: Pat Conlon on December 06, 2016, 10:15:40 PM
Some paper filters need no oil and should remain dry, some paper filters are designed for and need oil , like K&N.
This thread just keeps digging a deeper hole, and we still don't know what the difference between foam filter oil in a bottle and foam filter oil in a spray can is except you shouldn't use the one in the bottle........
(popcorn)
Noel
I have both filters, a K&N panel filter for my Miata and the UniPods for my FJ, so I can tell you the difference between the K&N filter oil and the foam filter oil.
The K&N filter oil is a lighter body oil, the foam filter oil (I use PJ1) has a heavier body and as Mark said, more tacky, more adhesive allowing the oil to stick better to the more porous foam.
K&N oil on foam does not stick and thus does not last long. Motor oil on foam does not stick (and can degrade the foam) Whether it's paper or foam, oil is most important for the filtering ability (excepting dry paper filters)
There are several discussions on the web which also share my conclusions if you care to search.
How come it seems any topic involving oil causes such confusion?
My point is simple: Follow the manufacturer's specifications. They know more than you do. They know what they designed their filters to use.
Foam filter oil is different than paper filter oil so use either appropriately.
http://www.uniflow.com.au/contents/en-us/d312.html (http://www.uniflow.com.au/contents/en-us/d312.html)
Your engine will thank you.
Noel, I've never seen foam filter oil in a bottle....I've always used a spray. In the past I've used the UNI, PJ1 and BelRay foam filter spray (oil)**.
** for Marty
The foam filter oil does come in can (bottle) UNI (http://adrenalineworld.com/uni-foam-filter-oil-16oz-uff-16/?gclid=CjwKEAiAg5_CBRDo4o6e4o3NtG0SJAB-IatYS7XUX17-PrBMGXDBuYyGI0KbagI7WuInIHUkF2gzKRoCbJTw_wcB)
Thanks Mark, I'll try that when my current can of PJ1 runs out. Looks to be a better deal at 16 oz vs 5.5 oz in the spray.
Quote from: FJmonkey on December 07, 2016, 11:40:55 AM
The foam filter oil does come in can (bottle) UNI (http://adrenalineworld.com/uni-foam-filter-oil-16oz-uff-16/?gclid=CjwKEAiAg5_CBRDo4o6e4o3NtG0SJAB-IatYS7XUX17-PrBMGXDBuYyGI0KbagI7WuInIHUkF2gzKRoCbJTw_wcB)
That's what I'm using for my UNI foam filter, that replaces the OEM filter used in the air box.
Quote from: Pat Conlon on December 07, 2016, 11:27:48 AM
How come it seems any topic involving oil causes such confusion?
Pat, the only confusion is continually referring to cotton gauze filters as "paper filters you oil". A number of people (5) have subtly made this point already, and yes, the oil for gauze is different from foam as you pointed out.
There are 3 types of material used in air filters,
paper you oil is not one of them.
Quote from: Pat Conlon on December 07, 2016, 11:27:48 AM
Noel, I've never seen foam filter oil in a bottle....
Pat, it's all I ever use, I think Uni even sell it by the bottle as do Motul, Belray, Castrol etc. Like anything in an aerosol, it's expensive by volume in a spray can.
I warm the oil by standing in a jug of hot water to thin it down, put the filter in a ziplock bag with the oil, work it well through, cut the corner off the bag (with it still sealed), squeeze the excess back into the bottle, remove the filter and squeeze it again in an absorbant rag then clean the flanges with whatever to remove oil so they don't slip off.
I never give them a final rinse in detergent and water before oiling. Unless you can be sure they are 100% dry, which is difficult to determine, the oil will trap the water and IMO, that can degrade the foam.
Noel
Oh...ok, got it...K&N is cotton gauze, not paper... My bad.
Good tip on the bottled UNI oil... :good2: