What did you do to your Marina today?
Moderators: ClaytonSpeed, balmy
- locost_bryan
- Posts: 3087
- Joined: Fri May 22, 2009 2:43 am
- Location: Auckland, New Zealand
Re: What did you do to your Marina today?
Nice pair.
Bryan
Auckland NZ
1972 Morris Marina 1750 TC Coupe "Ozzy"
Auckland NZ
1972 Morris Marina 1750 TC Coupe "Ozzy"
Re: What did you do to your Marina today?
Oh dear. Kermit is not well.
Yesterday noticed tappet noise on start up which quickly disappeared.
Investigated today to find oil low - very low.
usual suspects eliminated - little oil visible on drive, engine cleanish, sump and rocker cover not saturate, no foaming in water etc.
However rather oily soot deposits on garage door behind exhaust points to internal trouble. So suspect bore/piston trouble or valve guides.
A small amount of smoke but not excessive so more investigation needed. Sigh!!!!
Yesterday noticed tappet noise on start up which quickly disappeared.
Investigated today to find oil low - very low.
usual suspects eliminated - little oil visible on drive, engine cleanish, sump and rocker cover not saturate, no foaming in water etc.
However rather oily soot deposits on garage door behind exhaust points to internal trouble. So suspect bore/piston trouble or valve guides.
A small amount of smoke but not excessive so more investigation needed. Sigh!!!!
Re: What did you do to your Marina today?
Sounds good.ClaytonSpeed wrote: ↑Mon Aug 22, 2022 3:01 pm Sorry!
If you wanted one made up as a spare (I've a spare ring or two) let me know.
Re: What did you do to your Marina today?
Hoping to learn more about Kermit's thirst for oil have bought a compression tester & have tested the cylinder pressures.
Doesn't look good. Pretty consistent values, albeit possibly low, across cylinders but two rise when a squirt of oil injected through spark plug port .
Tending to think bores/rings worn and 2 valve guides shot!
Doesn't look good. Pretty consistent values, albeit possibly low, across cylinders but two rise when a squirt of oil injected through spark plug port .
Tending to think bores/rings worn and 2 valve guides shot!
- MarinaCoupe
- Posts: 10197
- Joined: Thu May 31, 2007 5:26 pm
- Location: Bedford
- Contact:
Re: What did you do to your Marina today?
The oil raising the compression pressure definitely points to piston rings. Just a thought though is the engine a low compression Van/Pickup unit or a higher compression Passenger car unit? Do you have your actual readings?
Re: What did you do to your Marina today?
Have been told compression reading should be around 175psi. Looks like rings need replacing. Sigh!MarinaCoupe wrote: ↑Mon Oct 24, 2022 8:06 am The oil raising the compression pressure definitely points to piston rings. Just a thought though is the engine a low compression Van/Pickup unit or a higher compression Passenger car unit? Do you have your actual readings?
- MarinaCoupe
- Posts: 10197
- Joined: Thu May 31, 2007 5:26 pm
- Location: Bedford
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Re: What did you do to your Marina today?
Hi, I just looked up the compression readings in the BL Marina & Ital manuals for the 1.3s.
Marina/Ital 1.3 1971 to 1984
Saloon, Coupe, Estate
Low Compression engine should show 170 psi (Compression Ratio 8.0:1)
High Compression engine should show 190 psi (Compression Ratio 8.8:1)
Commercials - Van & Pickup
Low Compression engine should show 150 psi (Compression Ratio 8.0:1)
High Compression engine should show 170 psi (Compression Ratio 8.8:1)
Obviously, these figures are for new engines of standard bore, the difference between low compression and high compression is achieved by the use of different pistons (greater or lesser dish in the piston top surface). Of course, this was when new. Every time you have a cylinder head skimmed, you reduce the volume of the combustion chamber in the cylinder head, so you increase the compression ratio, every time you rebore an engine, you increase the swept volume and this lowers the compression ratio slightly. With engines now between 51 and 38 years old, most will have had the head skimmed and/or block rebored at least once, also without dismantling the engine you can't tell which pistons have been used in previous rebuilds, so your actual compression ratio will be different from original standard.
On my old Pickup, I was using an engine from a 1.3 Ital saloon, so high compression pistons (i checked), it was bored +20 thou and the head had been skimmed several times, my compression readings ran between 210 psi and 195 psi, making it really difficult to set the timing and higher compression needs changes to the ignition timing.
There is I think an anomaly in the BL figures, as I can't work out how by using the same pistons, that the psi rating are different between the passenger cars and commercials. The passenger and commercials use the same cylinder head part number and the same gasket part number, so I would expect the same combustion chamber volume and the same thickness of gasket (also adds to combustion chamber volume). It would suggest that the passenger car cylinder heads had a slightly smaller combustion chamber by design or by skimming the head during manufacture, but there is no information on this at all.
Any who - a target psi rating of 175-180 is a reasonable level, variation of 5'ish percent from cylinder to cylinder would be acceptable.
Marina/Ital 1.3 1971 to 1984
Saloon, Coupe, Estate
Low Compression engine should show 170 psi (Compression Ratio 8.0:1)
High Compression engine should show 190 psi (Compression Ratio 8.8:1)
Commercials - Van & Pickup
Low Compression engine should show 150 psi (Compression Ratio 8.0:1)
High Compression engine should show 170 psi (Compression Ratio 8.8:1)
Obviously, these figures are for new engines of standard bore, the difference between low compression and high compression is achieved by the use of different pistons (greater or lesser dish in the piston top surface). Of course, this was when new. Every time you have a cylinder head skimmed, you reduce the volume of the combustion chamber in the cylinder head, so you increase the compression ratio, every time you rebore an engine, you increase the swept volume and this lowers the compression ratio slightly. With engines now between 51 and 38 years old, most will have had the head skimmed and/or block rebored at least once, also without dismantling the engine you can't tell which pistons have been used in previous rebuilds, so your actual compression ratio will be different from original standard.
On my old Pickup, I was using an engine from a 1.3 Ital saloon, so high compression pistons (i checked), it was bored +20 thou and the head had been skimmed several times, my compression readings ran between 210 psi and 195 psi, making it really difficult to set the timing and higher compression needs changes to the ignition timing.
There is I think an anomaly in the BL figures, as I can't work out how by using the same pistons, that the psi rating are different between the passenger cars and commercials. The passenger and commercials use the same cylinder head part number and the same gasket part number, so I would expect the same combustion chamber volume and the same thickness of gasket (also adds to combustion chamber volume). It would suggest that the passenger car cylinder heads had a slightly smaller combustion chamber by design or by skimming the head during manufacture, but there is no information on this at all.
Any who - a target psi rating of 175-180 is a reasonable level, variation of 5'ish percent from cylinder to cylinder would be acceptable.
Re: What did you do to your Marina today?
Thanks for all the info.
As stated elsewhere will prob plump for a rebuild in the New Year.
As stated elsewhere will prob plump for a rebuild in the New Year.
Re: What did you do to your Marina today?
On a side note the resilience of the A series in that it still works, even when worn, is an advantage. Only had to sort one when oil consumption could be calculated as low miles to the pint; driven carefully wasn’t noticeable, accelerate hard and there was an shall we say emission of haze.
Re: What did you do to your Marina today?
Thats what happened to the B series in my first Marina. Ended up using as much oil as it did petrolmarina12 wrote: ↑Sun Nov 27, 2022 11:13 am On a side note the resilience of the A series in that it still works, even when worn, is an advantage. Only had to sort one when oil consumption could be calculated as low miles to the pint; driven carefully wasn’t noticeable, accelerate hard and there was an shall we say emission of haze.
1973 Morris Marina Deluxe Coupe - 1750cc E Series - NZDM
https://tasteslikepetrol.net/
https://tasteslikepetrol.net/
- locost_bryan
- Posts: 3087
- Joined: Fri May 22, 2009 2:43 am
- Location: Auckland, New Zealand
Re: What did you do to your Marina today?
Just realized it's been 18 months since the last time I started Ozzy. Flooded first attempt, and took a fair bit of cranking before he finally fired up. Running very rough, probably needs fresh fuel.
Bryan
Auckland NZ
1972 Morris Marina 1750 TC Coupe "Ozzy"
Auckland NZ
1972 Morris Marina 1750 TC Coupe "Ozzy"
Re: What did you do to your Marina today?
Does this mean more progress soon?locost_bryan wrote: ↑Sat Dec 03, 2022 2:55 am Just realized it's been 18 months since the last time I started Ozzy. Flooded first attempt, and took a fair bit of cranking before he finally fired up. Running very rough, probably needs fresh fuel.
1973 Morris Marina Deluxe Coupe - 1750cc E Series - NZDM
https://tasteslikepetrol.net/
https://tasteslikepetrol.net/
Re: What did you do to your Marina today?
Collected this on 1/1.
Has been stored for me by friends for many years.
Good to have it back home.
Has been stored for me by friends for many years.
Good to have it back home.
Marina 6 one day,V8 the next
- JubileeNut
- FMM Supporter
- Posts: 5181
- Joined: Tue Jun 05, 2007 7:14 pm
- Location: Worthing, West Sussex, UK
Re: What did you do to your Marina today?
What going in that one? straight 6 or V8?
" Pru, Its Kicking off "
1973 Morris Marina TC Jubilee
2013 BMW 328i M Sport F31
1973 Morris Marina TC Jubilee
2013 BMW 328i M Sport F31
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- Posts: 1119
- Joined: Thu Feb 26, 2009 6:01 pm
- Location: Socialist Republic of South Yorkshire