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Mick  ntc

Valves inserts and guides were fitted when the head was reworked.

I was thinking of putting the head back on and doing a compression test but maybe I will look at the head first since you thought the petrol test  was too fast.

I have a new gasket now and dont mind taking the head off again it off again if I need to look at the bottom end but if we start on that the engine will end up coming out .

I will see if there is a ridge in the bore.

I have found a few other problems To be sorted including a failed cork seal on the front Carb. 

Looking at Rogers point about the plugs and reading the forum chat I will try new plugs as well.

Ewan 

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Hi Ewan,

I had terrible trouble with NGK plugs about 4 years ago.

After about 1000 miles (one month use) they would go off the boil.  If I had to change down to 2nd and then apply power the engine would hold back until some decent revs were found.

I changed to Champion L87 and the problem disappeared - and they last for nearly 5000 miles.

I have read somewhere that modern plugs do not have the same glazed finish to the ceramic insulator and our petrol wet engines kill them.

 

Roger

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6 minutes ago, RogerH said:

Hi Ewan,

I had terrible trouble with NGK plugs about 4 years ago.

After about 1000 miles (one month use) they would go off the boil.  If I had to change down to 2nd and then apply power the engine would hold back until some decent revs were found.

I changed to Champion L87 and the problem disappeared - and they last for nearly 5000 miles.

I have read somewhere that modern plugs do not have the same glazed finish to the ceramic insulator and our petrol wet engines kill them.

 

Roger

Roger 

Don’t get it I get 10000 miles out of the plugs I use NGK no problem 

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Hi Neil,

every engine is different. Perhaps mine is a little rich.

But the NGK plugs (from Ebay and Moss) lasted for a month or so.

The L87 from Moss last many times more.

Perhaps with EFI they may fare better with a leaner mixture. Something to dream of.

 

Roger

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2 minutes ago, RogerH said:

Hi Neil,

every engine is different. Perhaps mine is a little rich.

But the NGK plugs (from Ebay and Moss) lasted for a month or so.

The L87 from Moss last many times more.

Perhaps with EFI they may fare better with a leaner mixture. Something to dream of.

 

Roger

Roger 

I run Weber’s and plugs from Halfords

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The problem with NGK that your experiencing Roger is they dont like getting wet when new, this will kill them, use an old set until you have the engine mixture roughly correct then fit your new plugs, this has been well known for years.

Stuart.

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20 minutes ago, Ian Vincent said:

So what physical changes happen to an NGK plug when it gets wet when new as opposed to when it’s old. 

Rgds Ian

No idea just going by experience.

Stuart.

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I took the valves out of the head and they looked poor so I have ground them in the exhaust's took a bit of work.

three of the exhaust's had very thin seats and were pitted they  looked much better after grinding in.

I then cleaned everything and after replacing the valves put the head back on last night should see tomorrow how it goes. 

Two points I did look at the bores and the are worn and wavy near the top and the valve guides are worn but will look to tackle these at another time.

One worry is I noted the block is cracked at the front right stud you can just see it in the photo the bolt took the torque and it was probably cracked a long time before I had the car  as there is a slot in the stud thread presumably to get it in with water from the cooling system in the socket.

I will let you Know how it goes.

Ewan

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1 hour ago, ewan2 said:

I took the valves out of the head and they looked poor so I have ground them in the exhaust's took a bit of work.

three of the exhaust's had very thin seats and were pitted they  looked much better after grinding in.

I then cleaned everything and after replacing the valves put the head back on last night should see tomorrow how it goes. 

Two points I did look at the bores and the are worn and wavy near the top and the valve guides are worn but will look to tackle these at another time.

One worry is I noted the block is cracked at the front right stud you can just see it in the photo the bolt took the torque and it was probably cracked a long time before I had the car  as there is a slot in the stud thread presumably to get it in with water from the cooling system in the socket.

I will let you Know how it goes.

Ewan

The standard studs have that slot machined in them as part of their original process (very good quality) and a hairline crack of the block into the waterjacket is the least of these 50 year old engines problems. Can be fixed either mechanically (no not welding) or by a wash to seal the block into the crack if it starts weeping.

Mick Richards

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47 minutes ago, T Rusty said:

As a TR3A driving, travel loving, bird watching amateur mechanic this post had it all. Mick, thanks for your very detailed answers. Lots of stuff in there I’ll re-read many times. Ewan let us know how things progress. Paul 

+1

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Every thing back together but only started after I found the fuel tap handle was broken and needed a spanner to turn it on it is a Revington fuel Tap and the handle broke. 

Did a compression test after setting the tappets and carbs. came up 180 180 170  190  front to back. Will re check the tappits tomorrow and put in new plugs I think it is sorted for now but need to plan for a full rebuild sooner than later. 

Mick thanks for the detailed advice even if I did not follow it all. 

 

Ewan 

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I was holiday today as I had been planning to go to the lakes weekend.

It has been chancled and accomodation is very thin on the ground so we are not going. It is only the last two years we have missed.

I have attended every lakes scince 1991 in the TR till last year.

Took the car out this afternoon once the rain had stopped. It was running great plenty of power and sounded normally loud.

Thanks all for your advice Sue hope you enjoy Whitehaven then Scotland.

Ewan :D

 

 

 

 

 

 

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20 minutes ago, ewan2 said:

I was holiday today as I had been planning to go to the lakes weekend.

It has been chancled and accomodation is very thin on the ground so we are not going. It is only the last two years we have missed.

I have attended every lakes scince 1991 in the TR till last year.

Took the car out this afternoon once the rain had stopped. It was running great plenty of power and sounded normally loud.

Thanks all for your advice Sue hope you enjoy Whitehaven then Scotland.

Ewan :D

 

 

 

 

 

 

Cool what a simple petrol test can show ;)

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On 9/3/2021 at 5:13 PM, ewan2 said:

 

Thanks all for your advice Sue hope you enjoy Whitehaven then Scotland.

Ewan :D

 

 

 

 

 

 

Thanks Ewan, we are on the ferry to Islay at the moment then staight on to the Jura ferry.

Sue

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On 9/1/2021 at 6:06 PM, DavidBee said:

+1

David, ihave started a separate thread under the “ Social Scene” headed forum topic with your name in the thread heading, for the photos of our ScottishTRip.

I tried to send you a pm ( private message here on this forum but I think your inbox must be full……………..

Sue

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5 hours ago, SuzanneH said:

David, ihave started a separate thread under the “ Social Scene” headed forum topic with your name in the thread heading, for the photos of our ScottishTRip.

I tried to send you a pm ( private message here on this forum but I think your inbox must be full……………..

Sue

Thanks Sue, GREAT! Really looking forward to seeing your photos. 

David

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On 8/30/2021 at 12:06 PM, Motorsport Mickey said:

Well I normally leave the petrol in the chambers overnight,

Is it not a potential safety problem leaving 4 open chambers full of petrol over night in the average sized garage?

When I had a railway arch one of my neighbors blew the back wall off their arch simply by leaving a small bucket of petrol on the floor and a lit candle on the other side of the room. (Obviously, it was not accidental.) After a few hours the air/vapor mixture was just right to cause the explosion.

I know we are not talking about a lot in the case of the cylinder head, but I still think it would be better to leave it in the garden overnight.

Charlie.

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On 9/2/2021 at 3:13 AM, ewan2 said:

Every thing back together but only started after I found the fuel tap handle was broken and needed a spanner to turn it on it is a Revington fuel Tap and the handle broke. 

Did a compression test after setting the tappets and carbs. came up 180 180 170  190  front to back. Will re check the tappits tomorrow and put in new plugs I think it is sorted for now but need to plan for a full rebuild sooner than later. 

Mick thanks for the detailed advice even if I did not follow it all. 

 

Ewan 

On the basis of this thread and the article on TS2 in TRaction I did a compression test today on my daily driver TR2. I raise it as it is very close to your result. 170. 168, 170, 180 front to back.

I was impressed. The head hasn't been lifted since 1994 and has done about 80,000 miles. It was running far to lean for a fair while too.

They are very robust engines.

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1 hour ago, Charlie D said:

Is it not a potential safety problem leaving 4 open chambers full of petrol over night in the average sized garage?

When I had a railway arch one of my neighbors blew the back wall off their arch simply by leaving a small bucket of petrol on the floor and a lit candle on the other side of the room. (Obviously, it was not accidental.) After a few hours the air/vapor mixture was just right to cause the explosion.

I know we are not talking about a lot in the case of the cylinder head, but I still think it would be better to leave it in the garden overnight.

Charlie.

Yeah…given the typical 50 odd cc in each chamber x 4 being very small I’ll risk it. Conversely the number of cats, birds and other garden inhabitants that can die after petrol ingestion, is also with us.

Maybe substitute diesel if you really want to test valve seat seals, the diesel is much more searching and also doesn’t suffer from the same air/ fuel volatility.

Mick Richards

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  • 1 month later...
On 9/7/2021 at 9:08 AM, John McCormack said:

On the basis of this thread and the article on TS2 in TRaction I did a compression test today on my daily driver TR2. I raise it as it is very close to your result. 170. 168, 170, 180 front to back.

I was impressed. The head hasn't been lifted since 1994 and has done about 80,000 miles. It was running far to lean for a fair while too.

They are very robust engines.

That article states that healthy TR engines should have compression of around 140-150psi per cylinder.  Mine are 123-124 (dry) so very even, but are they too low?

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It is impossible to compare two different compression gauges, they are not precision tools and are uncalibrated.   The best they can do, and do well, is compare cylinders across the block.  If all your cylinders are 123.5 +/- 5 then they are fine!

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