Sudden engine noise

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mkmskm

Sudden engine noise

Post by mkmskm »

We were about 1/2 mile from home after about a 100 mile drive when all of a sudden I heard a bit of a squealing and scraping sound. All the gauges looked good and the car ran fine so I parked it and when I opened the hood it appears to be coming from the right hand cam belt pulley and is engine speed dependent. Bearing issue or could it be just scraping the inside of the cover? Its too hot to handle right now so I'll look further when it cools down.
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124JOE
Posts: 3141
Joined: Fri Jun 24, 2011 7:11 pm
Your car is a: 1978 124 fiat spider sport 1800
Location: SO. WI

Re: Sudden engine noise

Post by 124JOE »

was that cam berring cap the hottest point at that time?
then id say its the berring.joe
when you do everything correct people arent sure youve done anything at all (futurama)
ul1joe@yahoo.com 124joe@gmail.com
So Cal Mark

Re: Sudden engine noise

Post by So Cal Mark »

the tc doesn't use cam bearings. Get a stethoscope to help pinpoint the noise. A scraping noise in the front is usually related to the timing belt cover
mkmskm

Re: Sudden engine noise

Post by mkmskm »

Found the issue. My smog pump locked up and the belt stripped all of its teeth and the now smooth belt was running around a cogged but frozen smog pump. For now I cut off the belt. I didn't see this part listed in IAP or Vick's but it does look like Rock Auto carries them. I'm guessing by looking at the timing cover I have to drain the radiator and pull that hose T off just to get the timing cover off. I guess I should have the timing belt replaced too - is that a do it yourself job?
131
Posts: 672
Joined: Sun Nov 14, 2010 1:13 am
Your car is a: 1982 131 Superbrava warmed 2.0 litre.
Location: Tasmania, Australia

Re: Sudden engine noise

Post by 131 »

If you disconnect the water outlet T without draining the block/radiator you'll only lose a bit of coolant, which will just require topping up when everything is back together. Unless of course you want to take the opportunity to give it a good flush and replace the coolant.
Mick.

'82 2litre 131, rally cams, IDFs & headers.
So Cal Mark

Re: Sudden engine noise

Post by So Cal Mark »

you must have a 75 or 76 year car, and you're very lucky that seized pump didn't take the timing belt off too. That is an interference engine and will bend valves if the t-belt fails. If you're not required to run the smog pump, I'd delete it. If you are required to run it, consider getting a set up from a 77 that drives the pump with a vee belt
131
Posts: 672
Joined: Sun Nov 14, 2010 1:13 am
Your car is a: 1982 131 Superbrava warmed 2.0 litre.
Location: Tasmania, Australia

Re: Sudden engine noise

Post by 131 »

mkmskm wrote:I guess I should have the timing belt replaced too - is that a do it yourself job?
It's quite easy if you're familiar with the procedure, but is quite daunting if you haven't done it before. If you don't know the history of your timing belt or it's done more than 15k miles I'd replace it while you have the cover off. There is a detailed write up of the procedure someone did recently on the forum, a quick search should bring you up to speed on what you're up against.

Mick
mkmskm

Re: Sudden engine noise

Post by mkmskm »

Yes the car is a '76. I live in Missouri so as far as emissions go they don't check that kind of thing here. In fact the car has year of manufacture plates on it so as long as I own the car it will never see the DMV again. I don't mind putting a new pump back on, as they are pretty cheap. As far as the timing belt history, it was on my to do list anyway because I have no history on it. The car has 42,500 miles on it, and the previous owner had it for 9 years and claimed it had been changed right before he bought the car but given the cars age and what just happened to this belt I think its time. I'll look for the procedure here, and I have an original shop manual I just purchased. I haven't messed with the timing belt before but at least it looks accessible.
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bradartigue
Posts: 2183
Joined: Thu Sep 20, 2007 2:35 pm
Your car is a: 1970 Sport Spider
Location: Atlanta, GA

Re: Sudden engine noise

Post by bradartigue »

Take off the pump, block it off, regain the HP. FIATs are very clean burners without that pump.
mkmskm

Re: Sudden engine noise

Post by mkmskm »

What is the hp gain without the pump?
131
Posts: 672
Joined: Sun Nov 14, 2010 1:13 am
Your car is a: 1982 131 Superbrava warmed 2.0 litre.
Location: Tasmania, Australia

Re: Sudden engine noise

Post by 131 »

mkmskm wrote:What is the hp gain without the pump?
3.72
Mick.

'82 2litre 131, rally cams, IDFs & headers.
fiat218
Posts: 5745
Joined: Fri May 16, 2008 5:06 pm
Your car is a: 1969 124 AS spider

Re: Sudden engine noise

Post by fiat218 »

when disconnecting a smog pump. is that all u do is remove the belt? is there other things to re route or remove/?
just wondering i have a 80' with a pump
Jim
East Grand Forks MN
1970 Fiat Spider BS1 ( FOR SALE
1969 124 AS Spider
2017 Abrath
2018 Alfa Romeo 4c Spider
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