Technical Popping exhaust
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Technical Popping exhaust
smart51
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Are both surfaces flat? If they rock when pressed together, there might be too much gap for the gasket to seal.
As far as the eye can tell they were. But guess not since it leaked again. I thought about adding loctite 5926 but on a facebook group this was not advised since the gasket should be able to do the job. 2 gaskets perhaps?
If both surfaces are flat then one normal gasket is sufficient.
Timing!!!!
I think I've cracked it! Originally when I bought the car it had a little plate/magnetic electronic ignition fitted, when that died and I went back to plugs and points I did gapping, valves and other basics. The car started and ran ok for a while and then my issues started and I put it down to fitting a bit of a boomy exhaust.
I did a bit of fiddling with the cap, just out of boredom, a slight twist anticlockwise and suddenly it came alive and a lot more responsive. Still the odd put-put-put but no where near as bad.
Second discovery, someone had put a return spring between the carb/throttle linkage to one of the valve cover studs, during my test revs this popped off and again the carb suddenly came to life, I wasn't getting anywhere near full throttle and stupidly the amount of times I had carbs on and off replacing this spring just became part of the process!!! When I use the pedal it sticks so I take it a previous owner didn't want to change the throttle cable. WD40 is a battle to keep hold onto in my place so I'm going to buy a can tomorrow and oil up everything throttle and link wise and pour a load into the cable itself from the engine end and see if it frees out.
An hour tonight has brought back the optimism!
Fiddle with your timing Flock, points gaps, static timing....the whole lot and see how you get on!
I think I've cracked it! Originally when I bought the car it had a little plate/magnetic electronic ignition fitted, when that died and I went back to plugs and points I did gapping, valves and other basics. The car started and ran ok for a while and then my issues started and I put it down to fitting a bit of a boomy exhaust.
I did a bit of fiddling with the cap, just out of boredom, a slight twist anticlockwise and suddenly it came alive and a lot more responsive. Still the odd put-put-put but no where near as bad.
Second discovery, someone had put a return spring between the carb/throttle linkage to one of the valve cover studs, during my test revs this popped off and again the carb suddenly came to life, I wasn't getting anywhere near full throttle and stupidly the amount of times I had carbs on and off replacing this spring just became part of the process!!! When I use the pedal it sticks so I take it a previous owner didn't want to change the throttle cable. WD40 is a battle to keep hold onto in my place so I'm going to buy a can tomorrow and oil up everything throttle and link wise and pour a load into the cable itself from the engine end and see if it frees out.
An hour tonight has brought back the optimism!
Fiddle with your timing Flock, points gaps, static timing....the whole lot and see how you get on!
the hobbler
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Ano
Another regular place for the throttle to stick is the bushes for the cross-bar between the throttle pedal and the little arm that the throttle-cable attaches to---would be worthwhile checking that. The only other place that the throttle cable can stick is where the cable runs through an 'outer' sheath, which is between the rear bulk-head and where the throttle cable attaches to the fan-shroud top-cover. It is not a difficult job to pull this outer sheath off, carefully clean the actual cable and try and get some "gunge dispersant" down the outer sheath. You must be careful, because if you put too much lubricant on the cable where it runs through the outer sheath, that lubricant can gather gunge which will make the cable stick.
Great you have found a possible cause and gained performance into the bargain
. In the 1970s working at a Lada Dealership after every service I would check and re position the throttle linkage, as often the second choke on the Russian copy Weber carb wasn't even moving.Customers were always impressed how much better their car went after the service
.With that stronger spring on your carb, is there any chance it is causing wear at the throttle spindle allowing air in, I have seen it on older Fords with Solex carbs.
I was shocked at the difference it's made so far, just 10 minutes of tinkering after not going near it for a few weeks.Great you have found a possible cause and gained performance into the bargain
Customers were always impressed how much better their car went after the service
With that stronger spring on your carb, is there any chance it is causing wear at the throttle spindle allowing air in, I have seen it on older Fords with Solex carbs.
The carb was recently rebuilt by a chap here in Ireland called Stewart Walsh who ran Team Little Italy which was Ireland's main Fiat restoration place so I think anything that may have worn he'd have either warned me about or indeed replaced.
He just passed away on Tuesday, I went to the wake last night in his home and that gave me the incentive to come home and mess with it. He's looking over me still.
In response to a request from an owner on another forum I put together a small number of static LED timing lights. I have two left if anyone is interested. They don’t take up any room but do the job. £11 posted in the UK. Red crocodile clip goes to the low tension feed, same as the condenser and black goes to any earth, simple as that.
I think I've cracked the popping too! After ruling out everything and reverting from "me not touching anything but the steeringwheel' to 'look at me, I'm a mecanic' today I replaced the exhaust manifold and .....the popping went away. It's gone. I stood for a full 10 min in the garage just smiling. My kids came home from school and I told them....you're looking at the popping stopping man. (one gave me the finger and walked away, the other asked if I could move because he needed his football.)
The last months the popping has been the centre of my life, so I kept the faulty manifold and I will treat it as a reminder never to give up. Oh the joy of actually accomplishing real stuff in my life.
The last months the popping has been the centre of my life, so I kept the faulty manifold and I will treat it as a reminder never to give up. Oh the joy of actually accomplishing real stuff in my life.
the hobbler
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Well done!
That is exactly where it was sticking, the cross bar. I took the 10's out, sidelined the tunnel cover and stood the cross bar upright and sure enough very little movement. Cir-clip off and just fed WD into it and worked it down into it side to side and then started working it back and forth, it's on the verge of spinning like a top now, going to leave it soak for the night. One of the 10mm bolts seems to be threaded so I'll probably have to drill and nut and bolt it.
A lot of small tweaks on these can reward mega results. Months of fighting and getting fed up followed by two nights of messing and I'm finally on the right track.
Thanks again to all for their suggestions and input!
Happy FR85!!
Recheck with the rag over exhaust tailpipe in case any leak has re appeared, it should stop the engine.
Major discovery today! So i met a follow 500 owner. I parked next to him, had my car idling and asked if he could turn the engine on so i could hear it. It was on he said. Wait...? Why is it so silent? Oh no, its not he said. It backfires because my i had my exhaust off and didnt screw it tight. Here, listen...he revs his engine i hear little cute pops.
He took me for a little spin round the block and we could actually talk and hear what was said.
Than i took him for a spin in my car. It sounded like a nascar compared to his car. Low resonating rumble and lots and lots of noise. He asked if i had 250hp in the engine compartment.
I quickly came aware that the sport exhaust i have on mine (bought it that way) is way way way to loud.
I explained to him that my popping and backfires were a real problem since i mainly drive small roads with lots of elderly People on bicycles on them. Each time i let go of the gas the cautiously pass them the car goes poppoppop BANG sending the old folks straight into the ditch.
So next thing to do...order a stock exhaust.
He took me for a little spin round the block and we could actually talk and hear what was said.
Than i took him for a spin in my car. It sounded like a nascar compared to his car. Low resonating rumble and lots and lots of noise. He asked if i had 250hp in the engine compartment.
I quickly came aware that the sport exhaust i have on mine (bought it that way) is way way way to loud.
I explained to him that my popping and backfires were a real problem since i mainly drive small roads with lots of elderly People on bicycles on them. Each time i let go of the gas the cautiously pass them the car goes poppoppop BANG sending the old folks straight into the ditch.
So next thing to do...order a stock exhaust.
smart51
Established member
I have a sport exhaust on mine, but a quiet one. Some of them are crazily loud.
I went from the noisy bang from a sporty exhaust to the same with a standard exhaust. Do have a check of your timing. I don't have another set of spare gaskets to go back to the boomy one to do an A/B between the two....
From the moment I got the car (a year ago) it was loud on the outside and inside. I just thought that was due to poor isolation in such an old car. I checked and reset the timing multiple times, and that ain't the problem. From the moment I got the car it popped, the banging came later. The car makes such a loud noise that when working on it and revving the engine I feel sorry the neighbours. It is really really loud and has a deep rumble in it, like the tuned Civics and Astra's young men in their twenties have. I'm almost 50
I did wonder why on youtube video's the 500's did sound a lot more like little cars but actually never really thought about it because I didn't now better. So today i'm ordering a stock exhaust. They are cheap so why not, and hopefully with the new manifolds from the other day and a new exhaust I hope the popping/backfire also dissapear. If not, and they are like the 500 I saw and heard yesterday...who cares, that's peanuts compared to how it is now.
I did wonder why on youtube video's the 500's did sound a lot more like little cars but actually never really thought about it because I didn't now better. So today i'm ordering a stock exhaust. They are cheap so why not, and hopefully with the new manifolds from the other day and a new exhaust I hope the popping/backfire also dissapear. If not, and they are like the 500 I saw and heard yesterday...who cares, that's peanuts compared to how it is now.
