cant get above 4000 rpm

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Tappy
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Joined: Wed Apr 02, 2008 8:22 pm
Your car is a: 124 spider 2000 1979
Location: Belgium ; Centre Of Europe

cant get above 4000 rpm

Post by Tappy »

my spider doen't come above 4000 rpm

its a 2 l with double idf40's , breakerless ignition

I've replaced the ignition points and adjusted them for over 40 times now ,(dont have a strobe light or dwell meter :()

but still cant get more than 4000 rpm , where should i look ? i can see fuel beeing injected in the carb , there's ignition on all 4 sparks

can sombody point me out wat can be causing this ?

thx
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msrmd

Re: cant get above 4000 rpm

Post by msrmd »

I had a similar problem, but I don't think it is the same as yours since I have a naturally aspirated 71. I had a local mechanic replace the timing belt and motor mounts (I'm not that mechanically inclined...sorry, blasphemy on this sight I know). I soon couldn't get the engine above 4000. When I looked under the hood, which is a dangerous thing for me to do, I found that they had disengaged the linkage rod from its hole on the engine bracket. It was just flapping in the breeze and I am surprised that it would work at all. You will all be proud of the fact that I actually took out a wrench and fixed it myself. My problem was solved, but I'm not sure that this will have any bearing on yours since you have a fuel injected spider. Oops just re-read your message and see that it is NOT fuel injected. My bad..hadn't had my coffee :roll:
Last edited by msrmd on Sat Jul 26, 2008 12:16 pm, edited 1 time in total.
mdrburchette
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Joined: Wed Jan 25, 2006 5:49 am
Your car is a: 1972 Fiat 124 Sport
Location: Winston-Salem, NC

Re: cant get above 4000 rpm

Post by mdrburchette »

I don't know how you have your carb linkage set up but have you checked to make sure the cable is actuating the carb linkage full throttle?
1972 124 Spider (Don)
1971 124 Spider (Juan)
1986 Bertone X19 (Blue)
1978 124 Spider Lemons racer
1974 X19 SCCA racer (Paul)
2012 500 Prima Edizione #19 (Mini Rossa)
Ever changing count of parts cars....It's a disease!
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Tappy
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Your car is a: 124 spider 2000 1979
Location: Belgium ; Centre Of Europe

Re: cant get above 4000 rpm

Post by Tappy »

its a mechanical linkage , but that comes fine

just made a test drive , cant drive over 3000 rpm either and i hear a noking sound when i do get @3000 rpm

the spider also sounds more like a beetle then a fiat :s
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mdrburchette
Posts: 5754
Joined: Wed Jan 25, 2006 5:49 am
Your car is a: 1972 Fiat 124 Sport
Location: Winston-Salem, NC

Re: cant get above 4000 rpm

Post by mdrburchette »

It sounds like a fouled plug but I'm sure you replaced or checked the plugs.
1972 124 Spider (Don)
1971 124 Spider (Juan)
1986 Bertone X19 (Blue)
1978 124 Spider Lemons racer
1974 X19 SCCA racer (Paul)
2012 500 Prima Edizione #19 (Mini Rossa)
Ever changing count of parts cars....It's a disease!
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Tappy
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Joined: Wed Apr 02, 2008 8:22 pm
Your car is a: 124 spider 2000 1979
Location: Belgium ; Centre Of Europe

Re: cant get above 4000 rpm

Post by Tappy »

i didnt change them , but they all fire up fine ....i guess i got them out one bye one and tested them that way
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TulsaSpider
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Your car is a: 1978 Spyder 124 2L
Location: Tulsa, Ok

Re: cant get above 4000 rpm

Post by TulsaSpider »

Uhhh a knocking sound did you say? :shock: Like a heavy knock like a bad bearing? or a pinging like detonation? A rattle like a bad valve? Does this happen (the rev's only going to 3000) when the tranny is in neutral as well? Is it worse under load? All RPM's? How is it running ? Do you have a oil pressure guage? If so how's the pressure? Take a long extention or screwdriver and start the motor then put it to your ear like a stethoscope, that way you can hear what's happening very clearly, you might be able to tell what part of the motor is making the sound by checking all around, for example valves, intake or exaust, or down lower in the motor. Check accesories as well alt, air pump, etc.. Sorry but there are many possibilities with a "knocking in the motor but few of them are good news.. and hard to diagnose without being there that's why we have this wonderful site eh??
Good luck!
1978 Spyder 1800 make that 2L! Finally making real progress!
Zamise

Re: cant get above 4000 rpm

Post by Zamise »

I'm just learning about my fiat, have had some experience with motors but no means an expert. My first and thought is that the timing is off. Then maybe a carb adjustment is off. Was just putting my carb back on today, and one of the hoses for the choke that antifreeze runs through got cought behind the throttle preventing it from opening all the way. Lucky I cought it, well my dad cought it actually, but perhaps a possibillity on yours too maybe??? Would be nice for ya if it was something that simple. We even found a hose that had a ball bearing inside it plugging it up after we cut the tip off, got lucky there, would have never found it if the tip of the hose wasn't split. Why it was ever plugged hmm? Anyway, just goes to show you've got to check the unlikliest things sometimes too. Hope for your sake its not something bad. Knocking can be bad. If the timing belt jumped some teeth or something like that you don't want your valves hitting the cylender heads and breaking off. Also, if a rod gets loose, the things the piston attaches to, from wear or some other reason, prob not good either, it'll make a loud knocking sound. Also if a valve spring breaks the valve can drop down too and knock, bad news, cause knocking and blown engine etc. Hopefully its not any of those bad things. Good luck with it!
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Tappy
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Your car is a: 124 spider 2000 1979
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Re: cant get above 4000 rpm

Post by Tappy »

Hi great help , but not very promessing on the causes ...

so i began with the obvious and most optimistic , fixing the leak in one of the idf's , aldo ive replaced the old red diafragm (doest that mean its probably in there for over 20 jears ?) bye the newer black ones. However i've been told that these old red ones weren't that resitand to todays fuell they still looked fine , what didn't chear me up becouse that means it will still have a leak when i place them back
The fuel leaks on the starter and stuff fom underneath the accelerator pump , its dripping fast when stationairy running or on halt , when the car accelarates it doesn't , so any ideas where the leak can be ?

On the other side this wont resolve the knocking sound , i get back on that later

Anyhow it wasnt a bad idea to get the manifold and carbs off , seemed like the gasket was all worn out , in fact there wasnt many left of it Could be the couse of my untracable small waterleak , new one is ordered
there were no gaskets between , the carbs and the manifold either , i did order a whole revision set , so i'll replace these on the fly (i tought)
one of the prev owners used a kind of glue (liquit gasket ?) so everything was hold tight :( Getting it of is probably harder than getting it on , wile @it i can clean them (outside that is , if i pull them appart i probably need an ad on pieces soon or worse on a whole new set ...)

To get back on the knocking sound

when a while ago she ran perfecly , after 140 m/h race on the highway something blew? (dindt hear it do , just assume) when i drove her back home , i guessed the oil return gasket in the distributor , becouse the leaking oil on the exhoust gave that much smoke that i tought she would go up in flames ! , that oil dripped from under the delco cap ..

not having a oilpressure meter i cant really tell if the pressure is any good

Replacing that will probably dont resolve the rather ratling (then nocking) sound

So what else went wrong ? the contactpoints i've replaced and tuned fine while i was on evening course (oldtimer basics) where melt away, or at least the plastic thing that go's on the nok of the distributor. Done that before , so i've replaced them again , got a new selenoid (is that correct?) and greased the nok a bit. Not having a dwell , strobelamp or tach ( bye the way i'll post a wanted for those in another post) i only did it using those thin blades. i wonder how bad she is tuned
might be cousing the bad rpm

SO I'v got the 3 main ingridients for bad tuning : fuel , ignition and a misterious rattle

the low rpm i get can be of a bad ignition in combination with the bad fuell suply , but what i cant explain is why i only get to 4000 rpm when the tranny is in neutral , but when drive only goes up to 3000rpm and on that rpm the rattling begins (even when in neutral) @ least it isnt a tranny problem (i should guess)

why cant it be be just one thing that goes wrong on the same time ?

i really hope it resolves itself (o my god even for me that sound extremely optimistic) but it probably wont , so i've started noting some numbers becouse my motor seams to be a self built engine , compiled out as much as possible pieces on different cars

when the ignition is setted corectly (dwell , tach, strobelight)

and the webers back on (hopefully without leaking)
i can start to fix the oil seal from the distributor

when done all those i'll report back here and keep you all notified ,if the misterious sounds still excist , then we go from there

dont just cross your fingers , cross everything you have .... :lol:
Last edited by Tappy on Wed Jul 30, 2008 6:51 pm, edited 2 times in total.
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manoa matt
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Your car is a: 1978 Fiat 124 Spider 1800
Location: Honolulu, Hawaii

Re: cant get above 4000 rpm

Post by manoa matt »

Find and fix the fuel leak first. You don't want fuel leaking onto the starter, the alternator, or anywhere else. The car will go up in flames very quickly. You better keep a fire extinguisher or a 5 gal bucket and garden hose close by when testing.
mdrburchette
Posts: 5754
Joined: Wed Jan 25, 2006 5:49 am
Your car is a: 1972 Fiat 124 Sport
Location: Winston-Salem, NC

Re: cant get above 4000 rpm

Post by mdrburchette »

Like Matt says, get the fuel leak taken care of first. You didn't lose an adjusting screw or jet, did you? I had a similar problem and found that I forgot to tighten the lock nut on the bypass screw and it had worked it's way loose. You'll also need to get a timing light to make sure your timing is correct. Since the engine ran good before, I wouldn't be concerned at the moment about what parts are from what car. You may also want to check and make sure you can't move the distributor by hand. I've had the nut that holds the distributor secure work it's way loose and cause all sorts of problems. You may also want to be sure you don't have a vacuum leak at the carbs.
1972 124 Spider (Don)
1971 124 Spider (Juan)
1986 Bertone X19 (Blue)
1978 124 Spider Lemons racer
1974 X19 SCCA racer (Paul)
2012 500 Prima Edizione #19 (Mini Rossa)
Ever changing count of parts cars....It's a disease!
Danno

Re: cant get above 4000 rpm

Post by Danno »

manoa matt wrote:Find and fix the fuel leak first. You don't want fuel leaking onto the starter, the alternator, or anywhere else. The car will go up in flames very quickly. You better keep a fire extinguisher or a 5 gal bucket and garden hose close by when testing.
I'd be hesitant to use a garden hose on a gasoline fire if I were you....
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Tappy
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Your car is a: 124 spider 2000 1979
Location: Belgium ; Centre Of Europe

Re: cant get above 4000 rpm

Post by Tappy »

pff the fuel leak comes from the first carb , replaced the diafragm now it doesn't drip anymore , it poors out ....

any sugestions , i cleaned the carbs on the outside ... and the leak is bigger :(
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Zamise

Re: cant get above 4000 rpm

Post by Zamise »

Whole carb rebuild time maybe? Make sure the screws are fairly tight, didn't leave any loose ones and always tighten opposite screws first, don't go around in order which I've been told can cause gaskets and diaphrams to crinkle up, incase you didn't know already. Other than that maybe you got a bad diaphram or it ripped or something when you put it in?

I just rebuilt my carb, and it leaked the first time I tried to start the car. I prob have a difrent carb though it sounds like, but anyway figured it might of been the float stuck open for and letting gas pour out, which it was from just about everywhere, turned car off, then tapped on the carborator ontop of where the float bowl is with the butt end of a screw driver a few times and it unstuck and stopped leaking.

Probably not your problem, but figure wouldn't hurt to suggest.

Good Luck!

Zam
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Tappy
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Your car is a: 124 spider 2000 1979
Location: Belgium ; Centre Of Europe

Re: cant get above 4000 rpm

Post by Tappy »

Zamise wrote:...Make sure the screws are fairly tight, didn't leave any loose ones and always tighten opposite screws first, don't go around in order which I've been told can cause gaskets and diaphrams to crinkle up, incase you didn't know already. Other than that maybe you got a bad diaphram or it ripped or something when you put it in?....
that is excatly what happend , the diaphram was ripped :( a new one ordered , put in the old one for now , still leaking but drips now , @ least i'm able to put the spider on the other side of the street , so i can get in and out the garage
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