How to tell when you have blown your head gasket!

**John M** · #1 (**permalink**) 11-02-2003, 04:18 PM

If your car looks like this:

**John M** · #2 (**permalink**) 11-02-2003, 04:21 PM

Or if it looks like this!

In all seriousness...I am glad this happened. Those of you who may remember my saga of gremlins in the water jacket is finally solved. I am going to pull the head tonight and get at it. On a happier note, I rejetted the carbs today. I had stock 152 45mm webers on her. I have moved to a 40 pump jet, and a 200 air corrector. She was running like a scalded dog right before she went!

Now back to the drawing board.

Best Regards,
John M

mtiso · #3 (**permalink**) 11-02-2003, 04:28 PM

sorry to hear that

**John M** · #4 (**permalink**) 11-03-2003, 05:36 PM

Well....its all in owning an alfa. This all started yesterday evening. Well...took everything off the head to prep for pull last night and this afternoon I got motivated to pull the head.

Before:

And just now.

Oh well, off to get her pressure tested tomorrow.

Best Regards,
John M

**John M** · #5 (**permalink**) 11-03-2003, 05:36 PM

And another

**papajam** · #6 (**permalink**) 11-03-2003, 06:37 PM

So what's the gasket look like?

**John M** · #7 (**permalink**) 11-03-2003, 08:05 PM

Hey Papa:

It was in pretty good shape. I found only one questionable area on #1 on the exhaust/block side of the gasket. Here is a picture. What do you think? She was smoking at idle and on decel after warmed up. Wouldn't smoke on accel. I am still going to pressure test and check for flatness of the head and resurface if necessary.

This picture is of the gasket on exhaust head-side of #1.

Best Regards,
John M

**John M** · #8 (**permalink**) 11-03-2003, 08:13 PM

And here is a picture of the gasket on exhaust block-side of #1.

gotglasses · #9 (**permalink**) 11-03-2003, 08:42 PM

That sure looks like a burn out on the gasket. Makes me wonder - there seems a lot of carbon on pistons, and a bit of burnt blue on the gasket. HMMMMM - Are you jetted correctly - Webers are great but they can be all over the lot on mixture. ' This looks like car loaded up at low speeds - which could be from sucking in oil on overrun or from rings and then ran too lean at high speeds to overheat the gasket.

I always retorque my head at the change of seasons and find that it helps to avoid a lot of grief.

**John M** · #10 (**permalink**) 11-03-2003, 09:03 PM

Hey Gotglasses:

Welcome to the board. She was running rich especially at upper RPMs at WOT. I was running 45 DCOE #152s out of the box. The gasket problem had begun to show itself back in July by overflowing the overflow. Block test kept coming back negative as well as compression test. So it finally went. But just this day that the gasket went, I had went from a 45 pump jet to a 40 and replaced the 155 air correctors with 200 airs. I had resynch and adjusted the mixture from 2 1/2 turns to 2 1/4 turns out on all cylinders. Very smooth idle. I left the rest the same. 145 mains with 36 vents. It was much much better. And I went out and really opened it up with the gasket weak. It ran like a top. Best it had ran in a year. And as you can tell with the carbon buildup remaining on piston #1, I found the problem almost immediately. So off to the machine shop to make sure the head is AOK.

Best Regards,
John M

**John M** · #11 (**permalink**) 11-06-2003, 04:52 PM

Well here is the latest news:

Head checked out to be flat. Pressure test showed no leaks. All valves sealing correctly with no leaks. Still took 4 thousandths off the head to remove very minor pitting around the water jacket of #1. I also took this opportunity to repair and replace and bad exhaust studs. She used to have bolts for the exhaust manifolds and they are a PIA to use with headers. With studs it is so so much easier to install headers. A little tig welding to repair previous damage to a couple of stud holes and then inserts.....(not helicoils). My total machine bill between the two shops...$175.

Cleaned the entire engine bay. Flow tested the radiator for the second time in as many months at a second shop and they say its fine.

I had my friend who works for Bosch Rex Rothe come to the house with a $3000 piece of calibrated granite and a $1500 dial gauge to measure the sleeve heights and they are in specs. But he took the granite and gauge with him.

Ordered a small list of items from are friends at IAP. New intake manifold. Already had an IAP HG sitting on the shelf. Got the vitreon?? "o" rings for the HG roll pins. New distributor cap and rotor. New thermostat. And the cam degree card.

Called RML this evening and also getting the 8.5 performance wires as well as the RML distributor. Seems like the advance curve might make a difference especially compared to a points distributor's advance mechanism and play after a couple of decades of use. 30 deg of max advance with the RML and its a 12 volt optical pickup that plugs directly into the MSD without needing another box. Plus the advance curve should better match the carb setup. I am hopeful I will fill it in the seat of my pants in the car as much as I felt it in the seat of my pants this evening. Cha Ching! One thing I will add about RML, they know their business. The guy I talked to there was extremely knowledgeable on every topic I threw at him. I think its fair to say that this is one of our suppliers we should consider more often when looking for performance upgrades, from ignitions to turbo and supercharging.

So I will have a decent marelli points distributor with new cap and rotor...and new condensor for sale soon if anyone is interested.

I am feeling very lucky as it seems to be turning out all good news. No problems in the head. Its all cleaning up nicely and be back together this weekend.

Best Regards,
John M

gotglasses · #12 (**permalink**) 11-08-2003, 08:58 PM

The machine work was really reasonble - that always impressed me with Alfas - maybe the aluminum is faster to work on ?

I once had a similar experience and burned a hole in a piston in only a few miles - they run really good on top when they are leaned out too much.

**John M** · #13 (**permalink**) 11-09-2003, 01:12 AM

I was pretty pleased with the resurface and pressure test for $75. And he also checked all the valves for sealing as well. I was worried about a crack somewhere that had been missed.

Ouch.....hole through a piston makes a huge mess...oil gets pumped out of the block and all over the engine bay if the hole is big enough. When my original stock engine died, it too developed a hole the size of a quarter slot along the side of the piston. Most likely due to broken rings/ HG failure. That was with shankle sk racing setup from the PO. They were 40s.

Since then I went to a 10.4:1 build up with oversized valves, 11mm cams, cut head, port/polish, and the 45s. Actually, I am not running too lean. I have a colortune kit to adjust my mixture. I also did not detect any detonation after the jet swap. From what I saw with the colortune, when I went WOT the Webers really go rich.

Most of the setups you will find utilizing webers whether 40s or 45s will go with a pumpjet of 35 or 40. Mains are dependent on venturi size. I am currently running a 36 vent with 145 mains. Airs are recommended to be mains + 50 = 195 and I am running 200s. My Webers came fitted with 155 airs and those make the car run extremely rich. I actually got a spread of airs....200, 210, and 220.

HG was most likely already weakened since either a HG leak or an exhaust stud in the water jacket has been intermittenly compressing the coolant system and kicking coolant out the overflow (especially after a 2 stop cool night drive). That has happened at least 4 times since July. Whether the stud caused the problem, or maybe unresolved pitting on the head from last time that wasn't machined out, I am confident that its all good now. The studs have all been checked and repaired as necessary. The pressure test showed that the suspect stud did not leak though prior to repair. Head was pressure tested, checked for flat...and it was, and .004 off for some minor pitting around the suspect failure area. Radiator has been flowed twice by two different shops. Recently new thermostat replaced with new IAP one. Going to RML distributor to better control advance. Hopefully, I have crossed my Ts and dotted my Is and this HG will take. This time I will chalk it up to the weakened HG just gave up after an all out WOT run up to 6000-6300 in gears 1-4. If it does it again, I think I will give copper a try.

Best Regards,
John M

**John M** · #14 (**permalink**) 11-12-2003, 11:26 PM

Yet again...put back together...

Best Regards,
John M