Technical Headgasket NOT blown, what's going on?

[vitorio]

Hi guys, sorry to bother you once again, but i am pretty confused here.

I bought my cinq for a steal with what the seller told me was a blown head gasket (a common ailment for FIRE engines, so i believed him right away). When trying to start the engine it ran very rough/on 3 cilinders and produced some good amount of white smoke.

On tearing it down, the leftmost cilinder looked to be rather oily/wet, the plug was wet/oily as it came out, and there was a good amount of oily gunk in the plug-well on that side of the block. Now i finally got my head off (after doing battle with a stubborn headbolt for a few nights), the gasket doesnt look like it's blown. It does look rather grubby, and cilinder 1 is dirty-wet, where as the rest is just dirty.

pics: https://picasaweb.google.com/106739504268479316664/Cinq02?authuser=0&feat=directlink

any ideas on what might be wrong here? i'd hate to put it all back together to find out something else entirely is wrong

any tips on cleaning the head and the mating surfaces by the way? there is a lot of carbon deposits on the valves and such

 

[David C]

Were cylinders 2 & 3 that clean when you took it apart?

 

[woj]

I am not a specialist in diagnosing internal engine problems, but:

Did you do a wet and dry compression test before taking everything apart?

In the currect situation I would strive to check that the piston rings are ok on cylinder 1. The first attempt would be to pour in some kerosene into the cylinder and check how fast it leaks through. If this gives you any doubts I would start considering taking the engine apart and replacing the rings. But again, I am no specialist here, I gave my engine to a professional and payed good money for the peace of mind

Another option is that there was simply a major water leak to the cylinder when somebody assembled the engine, and the gasket never had a chance to really properly blow

 

[vitorio]

Were cylinders 2 & 3 that clean when you took it apart?

Those pics were taken immediately after i lifted the head, no cleaning was done.

I am not a specialist in diagnosing internal engine problems, but:

Did you do a wet and dry compression test before taking everything apart?

In the currect situation I would strive to check that the piston rings are ok on cylinder 1. The first attempt would be to pour in some kerosene into the cylinder and check how fast it leaks through. If this gives you any doubts I would start considering taking the engine apart and replacing the rings. But again, I am no specialist here, I gave my engine to a professional and payed good money for the peace of mind

Another option is that there was simply a major water leak to the cylinder when somebody assembled the engine, and the gasket never had a chance to really properly blow

Nope, didnt do any compression testing. Piston rings could be the problem, but i seriously hope not, tackeling a head gasket for my first engine job was ambitious enough, i dont feel like having to revise/swap the entire block yet, i havent even driven the thing for more then 100 yards yet

 

[whitz]

you say lost of crap around the plug?

did you clean that all off and inspect HT lead for a break in them near the end as it could of arc to the head and cause a missfire

possible you mistook steam for white smoke?

Ash

 

[vitorio]

you say lost of crap around the plug?

did you clean that all off and inspect HT lead for a break in them near the end as it could of arc to the head and cause a missfire

possible you mistook steam for white smoke?

Ash

I havent inspected the HT leads closely, but i havent noticed anything special on them whilst taken them off. I would feel properly stupid taking the entire thing apart and finding out i could've fixed it with a new lead.

As for the steam/smoke, definitely a possibility, i'm not exactly an expert when it comes to engines, so i pretty much took that as a sign that something was seriously wrong. Wouldnt both white smoke and steam mean cooleant in the cilinder though?

 

[David C]

Those pics were taken immediately after i lifted the head, no cleaning was done.

Clean pistons usually mean they have had coolant in them.

So I'd say gasket failure allowing coolant into cylinder 2 & 3.

When I did the head gasket on my 899 Cinq, the failure point had the appearance of just a tiny scratch on the head, but it was enough the allow coolant to be sucked in when the throttle was closed.

I had three pistons covered in carbon (ie normal) and one suspiciously clean piston!

 

[woj]

Depending on the time of the year, a cold engine would produce certain amounts of steam naturally, water is a by-product of the catlyst process. Oil smoke is more easy to recognize, because it does not "dissolve" in the air that easy, stinks as hell, and has a characteristic color.

I prefectly understand your fears and headache about nailing the problems down. I actually had a couple of sleepless nights myself doing my covnersion thinking "what the hell have I gotten myself into? I have no clue about this stuff". The bottom line is you need to sort all this out while the engine is stripped and the access is easy, putting everything together and pray that it will work is not an option

EDIT: Why not take the HG to your skimmer, he should have enough experience in the eye to tell you if it's blown

 

[vitorio]

Clean pistons usually mean they have had coolant in them.

So I'd say gasket failure allowing coolant into cylinder 2 & 3.

When I did the head gasket on my 899 Cinq, the failure point had the appearance of just a tiny scratch on the head, but it was enough the allow coolant to be sucked in when the throttle was closed.

I had three pistons covered in carbon (ie normal) and one suspiciously clean piston!

I know, but i expected clean pistons to have no carbon at all, so i didnt suspect 2&3, even though they are a tad cleaner than 1&4, i havent inspected the head/gasket close enough that i would find tiny scratches, i was just surprised because i was expecting a good chunk of gasket to be missing on cilinder 1.

Depending on the time of the year, a cold engine would produce certain amounts of steam naturally, water is a by-product of the catlyst process. Oil smoke is more easy to recognize, because it does not "dissolve" in the air that easy, stinks as hell, and has a characteristic color.

I prefectly understand your fears and headache about nailing the problems down. I actually had a couple of sleepless nights myself doing my covnersion thinking "what the hell have I gotten myself into? I have no clue about this stuff". The bottom line is you need to sort all this out while the engine is stripped and the access is easy, putting everything together and pray that it will work is not an option

EDIT: Why not take the HG to your skimmer, he should have enough experience in the eye to tell you if it's blown

I know it wasnt oil smoke, i would've smelled/seen that, but looking at the head layout, i find it a bit unlikely that coolant would find its way into the cilinder seeing how most cooleant lines are on the outside of the block.

I will be taking the head to a skimmer anyway once i get it cleaned/stripped down, let's hope that i'm just missing a small notch or something

 

[David C]

...but looking at the head layout, i find it a bit unlikely that coolant would find its way into the cilinder seeing how most cooleant lines are on the outside of the block.

The coolant passages are close to all the cylinders. They are the long holes.

 

[vitorio]

The coolant passages are close to all the cylinders. They are the long holes.

Ah, i figured those were the oil returns, but i might be twisting some things over in my head, if those long holes are the coolant passages, that makes the blow gasket hypotheses a lot more likely

 

[David C]

Ah, i figured those were the oil returns

The oil returns are the large round holes around the edge of the block.

 

[vitorio]

The oil returns are the large round holes around the edge of the block.

yeah, i got those confused with the water lines.

Anyway, on closer inspection both the gasket, head and the block itself show browning/residue on the space between cilinder 1 and the upper water line, so i think it is indeed a blown gasket, just a tad more subtle then i was expecting.

I'll be bringing the head to the skimmers on tuesday, and i'll take the gasket with me so they can give it a look.

 

[levemircento]

on your pic

it looks like the fire ring has failed on no1 cylinder [fire ring is the metal ring/seal around the top of the cylinder on the gasket]

 

[vitorio]

on your pic

it looks like the fire ring has failed on no1 cylinder [fire ring is the metal ring/seal around the top of the cylinder on the gasket]

yeah, near the top is also where the brown gunk is and the gasket looks very manky, so i think it has failed there.

 

[cc1]

How many miles has the engine done?

 

[vitorio]

How many miles has the engine done?

The car has about 95k miles on it, and as far as i know, this is the original engine.

 

[cc1]

I would consider replacing the engine. Rebuilding can be expensive.

 

[vitorio]

I would consider replacing the engine. Rebuilding can be expensive.

Replacing is an option, i have a spare 1108 block lying around if the bottom end needs replacing. For now i'll take my chances on this one though, so how it does. Depending on how i enjoy the cinq over the summer i might consider swapping in something more spectacular during next winter.

 

[slugworth1987]

shame your not UK as im dropping mine in a few weeks