Alfa 75 1.8ie engine sound

Started by stuntmachine, May 08, 2020, 05:51:03 PM

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stuntmachine

https://youtu.be/E5jvSJd8miA

Can anyone tell me what is that grinding noise on idle? Or it sounds like it should?

Without belts
https://youtu.be/B-AiIMnvcrc

Cold start with new spark plugs
https://youtu.be/WKLHJaqSr_8

Reving
https://youtu.be/kOBbdpZk4Qk

And yes. I know. Dash is from older one 😂

And one more. When the engine is hot there is no pressure in coolant tank. It should be like that?




MD

#1
1 No coolant pressure when engine hot is not correct. The pressure should be checked via a "Leak Down Test" with a cold motor. No visible leaks may suggest a head gasket failure.
2 The cold start with no belts sounds like you have excessive bottom end bearing clearance issues. A mechanics stethoscope may help you in this regard to confirm initial diagnosis. https://www.youtube.com/watch?v=ReOFzsxD_lQ
Transaxle Alfas Haul More Arse.

Current Fleet
Alfetta GTV6 3.0
Alfetta GTV Twin Spark supercharged racer
75 1.8L supercharged racer

Past Fleet
Alfa GT 3.2V6
Alfetta GTV 2.0
Giulia Super 2.0
Berlina 2.0

stuntmachine

#2
But engine is quiet while Reving. So crnk bearings are fine. Somebody say that cham chain tensioner needs adjusting. I also find out now that colland cap won't hold pressure at all. I fill to full this reservoir and after it gets hot collant leaking all over from this cap. So that should be the case.


Have also problems with faymous pink cable that feed fuel pumps. No voltage on it while cranking it. Under the hood somebody done something in there. Two relays are yellow on left side. So probobly not a factory ones. Nr 3 are grey and nr 5 is white. There are two green  black cables going to one pin on relay. On green black is just cutted from it. But. This should go to starter motor relay? Because somebody change that and there is another relay that goes to starter motor and it is feed straight from battery.

When I move plate in afm there is no voltage on pink one in relay

I try to make it run after 5 years. In tank fuel pump is new and big one is leaking fuel from its casing. Any one  have magneti marelli one?

Colin Edwards

I'll admit my hearing is poor, however the engine seems quieter without the belts.  This (to me!) suggests a belt driven ancillary is at fault.  Possibly more than one?
If this is the first engine run for 5 years, its possible a dry bearing in one of the belt-driven components is contributing to the noise.  How does the belt tensioner, water pump, alternator or power steering pump feel when spun by hand?

A stuck alternator brush can squeal due to insufficient spring tension or poor slip ring surface condition.  Could be possible after 5 years of inactivity.  Wasps love to set up house in things like alternators!!
Present
2023 Tonale Veloce
2018 Abarth 124 Spider
1987 75 3.0

Past
2020 Giulietta Veloce
2015 Giulietta QV
2009 159 3.2 Ti Q4
2012 Giulietta TCT Veloce
2006 147 Ti 2 door Selespeed
1979 Alfasud Ti 1.5