79-2000- constant clicking

[wachuko]

The bosch plugs were broken. the ngk's were not crushed, wrong word. the gap was closed by "debris?" or a spun bearing? or something. Center electrode is still intact. I had gapped them, so I know the gap was open when installed. Later gap on at least one plug is closed. I was not concentrating on the plugs at that time but trying to set wheels to timing marks. MY gap issue happened before I disassembled the rad/fan hoses etc. I had run the engine with each plug wire off, one at a time, to see if the noise went away. No luck there.
The boroscope is a $400 tool and none of my mechanic buddies have one. I'll go with the light and have a look in the cyl.'s.

Please, for the benefit of the rest of the folks here, can you take photos as you open the engine to see the damage and root cause of the problem? Tks

[minimike]

I pulled all the plugs and peered into each cyl. I put a single strand copper wire from home wiring bent in the shape of an "L"
into each cyl, but felt no resistance. I was thinking that maybe the carb swallowed a stud and nut from the lower air cleaner bracket. Only 2 on the car.
Cyl's # 2 adn 3 rotate up to top and back down. #'s 1 and 4 will come to the top but get stuck in top position and I have to turn the engine back wards to lower the pistons.

does anything come to mind with 1 and 4 getting stuck? something with the aux shaft?

Can I remove the head with the carb attached? There's so much plumbing on this car, I'm hesitant to disconnect it all. Of course with a digi camera, and a marker, I guess I'll get it all back where it's supposed to be.

[ventura ace]

#'s 1 and 4 will come to the top but get stuck in top position and I have to turn the engine back wards to lower the pistons.

does anything come to mind with 1 and 4 getting stuck? something with the aux shaft?

It would be very easy to answer this question. Turn the engine to where it has the interference, then remove the timing belt so that you can wiggle the aux shaft back and forth to see if it is bumping (see my previous suggestion).

Alvon

[minimike]

Thanks. I'll give it a try tomorrow.

Also, I just saw the request for pix. I can take the pix. Someone here will have to walk me through posting the pix up, or I can em them to a member of the board and they can post them for me.

Pistons appear to be flat top.

[SLOSpider]

Starting from the beginning you said it ran but had a constant knocking. Did it run smooth or rough? I had a VW once that ran crappy sometimes and good at other times. I went to rebuild the carbs and found one of the throttle plate screws had came loose and was floating around the intake and once in a while would not allow the valve to close all the way. It is possible that something has fallin down into the intake and the valve is not being allowed to close thus the sticking ant the top end. You could start with removing the intake, its a bit easier to deal with the head removal with it off anyways.

[SLOSpider]

Thanks. I'll give it a try tomorrow.

Also, I just saw the request for pix. I can take the pix. Someone here will have to walk me through posting the pix up, or I can em them to a member of the board and they can post them for me.

Pistons appear to be flat top.

Best way to post pictures on any forum is to upload you pictures to an online storage place like photobucket.com. Once uploaded there will be an IMG link you can copy and paste right into your post on the forum.

[minimike]

I guess I'll try the aux shaft rotation with the belt off and see if I can turn the engine. The remove the intake. If I have to pull the engine it appears it will be lighter and lighter as I troubleshoot it. After the intake, I imagine I can get a good look into the cyl's. I was trying to avoid this due to all the vacuum lines on the carb. Ecch!

[So Cal Mark]

don't waste your time removing the intake, you can pull the head with both intake and exhaust attached.

[narfire]

I was trying to avoid this due to all the vacuum lines on the carb. Ecch!

Perhaps taking a couple of pics before pulling the lines would make installation easier, but you probably have already done that

[ventura ace]

Here's a few pics, that I took several weeks ago, while my 1.8L engine is apart at this time. The crankshaft is close to TDC for pistons 1 and 4 for this first picture, and close to the point where the aux shaft can hit #2 cylinder connecting rod bolt head. The intereference actually occurs when the crankshaft is closer to TDC than shown in this picture.




Close ups, with the aux shaft in place:
Aux shaft lobe bumping the connecting rod bolt: --------------- Aux shaft lobe rotated clear of the connecting rod:
-----

If this turns out to be your problem, you may not need to pull anything off the engine at all, just correct the timing, and hopefully that is it.

[minimike]

Alvon,

Great pix. Thanks. I got what you meant in the initial post, but the pix make it all very clear.

[BEEK]

unfortunatly i have experienced the stud thru the intake. in a carburated fiat, i have had a air cleaner mounting stud and nut fall out and get run thru the motor. ouch is all i can say, as this was a race motor and it looked like ground beef afterwards. what i did to correct this problem in the future was to remove all the studs and replace them with bolts run thru from the underside. then using new nylocks each time i never had a problem again. i know this wont make the problem any better , but it may offer you a suggestion for repairs to keep this from happening in the future

[minimike]

Beek,
I had a spyder about 30 years ago and always wondered if dropping a nut into the carb, or having one sucked in is an issue.
So here I am again with another car, and wondering how many fiat owners has this happened to? I'm planning to remove the studs, clean them, and put locktite on them. The nuts I believe are nyloc, and if they're tired, I'll replace them with new.
Thanks for the heads up.

[BEEK]

the only issue is the carburator top wears as its high zinc content and soft, the studs become loose even with locktite, thst the reason i run bolts up from the underside, the bolt head cannop make it thru the hole

[minimike]

Timing belt off, top cams aligned with marks, wrench on crankshaft pulley, and aux pulley loose and not the issue. Crank won't
make it to it's proper timing mark.

Should I remove the dizzy and carb to pull the head?
I''m thinking I should leave the head and just pull the engine at this point.