Blown head gasket / causes

[So Cal Mark]

sitting with a blown hg can allow water to etch the cylinder walls and of course there are several issues if that is the case

[baltobernie]

Hmmm well I am running the 9's now. I hope changing them out makes a good improvement!

What do the 9's look like now? And more importantly, are they all the same color?

[SanRafaelFaz]

sitting with a blown hg can allow water to etch the cylinder walls and of course there are several issues if that is the case

Oh, I should state that there was no water detected in the oil or other places where it shouldn't be, and the h/g just blew a short while ago. If that matters...

[131]

I have only about 40K on this NOS engine over the past 15 years. It sat for several years unused and I'm just now in the process of evaluating if I want to spend the $$$s to restore it.

If the bores are OK and there was no indication of a bottom end issue before the head gasket went, replace it and continue driving.

[TulsaSpider]

The plugs right now look like a rust color so they do look good . When we pulled the plugs last Sat after the head gasket blew I drove it about 8 miles or so and the tips on the non blown plugs were white ish. That could be due to the anomoly of the loss of comression between 2 and three though.

[TulsaSpider]

Well nobody seems to carry the RN6YC locally grrr apparently they cross ref an Autolite plug.. AR51 I wonder how that brand/plug is? Anybody?

[Sunracer]

I have had very good luck with NGK's and a lot of my FIAT buddies run the same, you should be able to cross to that.

[TulsaSpider]

They don't seem to carry those locally anymore. Do you have a number that is a colder plug by a factor of 2 or 3?

[htchevyii]

I looked at the o'reilly web site and it showed a NGK bp6es, so a bp8es should be 2 heat ranges cooler, (NGK is backwards compared to most plugs ie: higher number is colder).

[Sunracer]

Trey is right, I would only go one level cooler though and you might even go for their Iridium model-they work great.

[TulsaSpider]

Update! My friend Kent said the only way to really know these motors are on time is to pull off the pulley and line up the marks on the crank seal housing and the mark on the crank cog that also matches the keyway


So I pulled it apart and sure enough it seemed to be two teeth off on the crank. I lined everything up and on reassembly rotated everything and it was good. I made a new timing mark I started up and the timing mark was off again! so I tore everything apart again. The crank marks were still lined up! So I decided that the pulley must be the culprit. I tried wiggling it and it wiggled! More exactly I figured out it was the keyway. I think it was low in the front so to speak. I took off the crank cog pulley, which was a big hassle but I finally got it off. I could not remove the keyway so I tapped it down in the rear. I test fitted the pulley on the naked crank and it went on just great this time.There was some damage to the rear of the keyway groove. I re-assembled everything and it seemed to be much more solid this time, everything lined up. The pulley was solid.

Started it, checked it, nothing had moved. I took it for a drive at 0 degrees and it was a dog but no pinging. I came back and advanced to about 10 btdc like normal and it ran great and no pinging that I could hear. SO I think I have her whooped, I spent five hours in the heat so I am not gonna drive it anymore tonight. I will take it out again tomorrow, just to re affirm. So chalk it up to another newby mistake I guess! I think I will still try a little colder plug though ... Thanks for the plug recommendations!

[Sunracer]

Good work that is a tricky problem you found there!

[TulsaSpider]

I specialize in tricky.. lol

[pastaroni34]

Looks like your plastic aux pulley is rubbing on the crank pulley. This probably contributed to the problem you're having, making the crank pulley look like it was torqued down, then of course loosing pre-tension as the pulley rubbed and wore.

Ideally you should switch to a rear guard aux pulley, the front guard is rather useless. I should have a suitable pulley around somewhere. Let me know if you need one and I'll send it your way.

The aux pulley has also undergone unnecessary strain running like this.. I would replace it, as I would not trust it, especially being plastic.

[TulsaSpider]

You picked up on the line it made Jason. Actually that happened when I first put it back together. I think it's good now.Although one of my friends at the meetup said that the pulley looked worn out. So a front lipped one is better?