12 replies to this topic

[Timcg]

Hi everyone, feeling really depressed about this.

 

1275, Hif44 carb, standard pretty much everything.

 

New distributor, new plugs and leads, carb recently set up from scratch, new battery, timing redone when distributor replaced.

 

So recently had lots of ignition problems but for the past month has been driving pretty sweet, although always felt down on power. Yesterday I pulled into the carpark at work and it started shuddering, shaking, running like a tractor.

 

Got the engine idling and pulled out the HT leads one at a time. Removing leads 1 and 4 made the problem much worse (so assume these are good), removing 2 and 3 made no difference. I swapped the plugs over and no difference. I could hear the spark in the leads too, so safe to say it's the cylinders themselves. I have just ordered a compression tester, but it seems pretty obvious what the problem is.

 

So this weekend it'll be the head off (I'm a bit scared) and I hope to see the gasket has blown between 2 and 3.

 

My question is, is this all it is likely to be? While I've got the head off, what else should I be looking for? I don't really know a lot about valves etc and my biggest fear is replacing the gasket and it not being fixed!

[sonikk4]

Compression test first before you strip the head off. If that shows a issue with compression then strip it apart. With the head off consider taking the valves out and relap them in. Also check to see if the guides are worn. If not change the valve stem seals and rebuild it all.

[cal844]

It will be bad plugs!! Test them!

Pull the leads off a plug, remove plug

Put the lead back on the plug, then rest it on the head, now get someone to crank it over whilkst you check for a spark

[robminibcy]

sounds head gaskety to me. If it was running fine then suddenly stopped running fine you can be pretty sure its the gasket. Issues with worn parts such as valves or piston rings will usually take ages to get worse (often years). Easy way to check compression now: take all spark plugs out then one by one put your finger over the hole while cranking the engine, if air pushes past you've got some compression, if it doesn't or is less forceful than other cylinders then you haven't.

Edited by robminibcy, 02 April 2014 - 08:47 PM.

[Timcg]

Yeah, the plugs are less than a month old and swapping 1 and 4 for 2 and 3 made no difference - cylinders 2 and 3 still bad, 1 and 4 still good, so it's not them. 

 

I've read a lot of topics on here before coming to this conclusion, so the weight of opinion seems to be no point skimming, on an unleaded engine there's no point/need in getting the paste out (compared to a leaded engine) so it was really, what else should I look for?

 

So new seals just to be safe/might as well? What do bad ones look like?

[sonikk4]

I would still lap valves in no matter what. You don't have to go mad on new seats and valves but still worth doing.

[Carlos W]

It will be bad plugs!! Test them!

Pull the leads off a plug, remove plug

Put the lead back on the plug, then rest it on the head, now get someone to crank it over whilkst you check for a spark

 

I like advice like this! Start simple! 

[Other-car-is-a-1275GT]

Timcg, on 02 Apr 2014 - 9:31 PM, said:

Got the engine idling and pulled out the HT leads one at a time. Removing leads 1 and 4 made the problem much worse (so assume these are good), removing 2 and 3 made no difference. I swapped the plugs over and no difference. I could hear the spark in the leads too, so safe to say it's the cylinders themselves. I have just ordered a compression tester, but it seems pretty obvious what the problem is.

 

So this weekend it'll be the head off (I'm a bit scared) and I hope to see the gasket has blown between 2 and 3.

 

My question is, is this all it is likely to be? While I've got the head off, what else should I be looking for? I don't really know a lot about valves etc and my biggest fear is replacing the gasket and it not being fixed!

 

What you have described is exactly what happened to me. 

Do a compression test, you should notice that 2 & 3 should be lower than 1 & 4. Sometimes one cylinder out of 2 & 3 can be lower/higher than the other. If so it is most likely the head gasket.

I presume you have a Haynes manual so follow the guide for the strip down of the head.

While you have the head off its worth checking the valves for pitting as well as what others have suggested.

Depending on how long you've been running it like this, you might find that where there is a engraved groove into both the block and the head where the hole was in the gasket. Light sanding can fix this just to make sure that it doesn't happen again.

Make sure that both the main block and head is free of dirt and gasket remains before re-build. (Kinda obvious i know but it happens)

Personally, i used this gasket for my 1275. http://oldskoolminis...products_id=526

It's a good idea to check the timing and mixture after rebuild. 

 

Hope some of that helped,

 

Adam

 

 

[Timcg]

Cheers for all the suggestions on this one. Head off and here's a pic of the problem. All sorted now and the car is running pretty sweet.

 

Still think the mixture and/or timing might be a little out, but that's another a topic for another thread

 

Ah well, it won't let me upload a picture. Needless to say, big hole between two and three

Edited by Timcg, 21 April 2014 - 12:56 PM.

[gazza82]

I thought I read the Payen Black head gasket was best one for 1275?

[Other-car-is-a-1275GT]

I thought I read the Payen Black head gasket was best one for 1275?

 

 

That one? Payen BK450

Apparently i can't hyperlink stuff correctly -.- That is what i have and should have linked... 

[gazza82]

Yes, that's the one .. is there anything better?

[Other-car-is-a-1275GT]

Yes, that's the one .. is there anything better?

 

Well there is a newer one that has superseded the BK450 which is this -> http://www.minispare...UG702560HG.aspx

The only difference is that the newer type has a special oil seal ring for the rocker supply. With saying that i still prefer the BK450 and would buy it every time.