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ALESSANDRO RAMIREZ GAMEZ
New User
Username: alessandro_rg

Post Number: 2
Registered: 04-2020
Posted on Monday, 24 August, 2020 - 07:58:   Edit PostDelete PostView Post/Check IP

Dear friends, I recently rebuilt the carburetor, cleaned the cooling system, and car runs perfect for 20/30 minutes, good compression, no leaks, no smoking.
After half and hour aproximately, engine starts losing power and smells oil with a little smoke. A mechanic suggested that spark plugs are getting oiled.
Might be rings problem or valve seals only. Any chance to remove the valve seals with heads on?, any special tool to avoid that valves fall down while doing this?. Please feel free to share your comments or suggestions. Thanks
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David Hughes
Experienced User
Username: wedcar

Post Number: 114
Registered: 07-2004
Posted on Monday, 24 August, 2020 - 09:12:   Edit PostDelete PostView Post/Check IP

Alessandro
First things first.
Run the engine to normal operating temperature then remove all the spark plugs and perform a compression test.
Faulty rings can be checked by adding a squirt of oil to the cylinder after doing the initial test and testing again.
There is a "hook like" tool (I don't have one) inserted through the spark plug hole to support the valve to enable the valve seals to be changed.
Regards
David
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ross kowalski
Prolific User
Username: cdfpw

Post Number: 1456
Registered: 11-2015
Posted on Monday, 24 August, 2020 - 10:00:   Edit PostDelete PostView Post/Check IP

Allesandro,

David is right, first diagnose the problem then fix it.

I would also do a vacuum test as well.
First at cold idle, then again hot when losing power.

FYI, valve seals have nothing to do with power and usually smoke most at startup.

A non firing piston will cause power loss and smoke as well.
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Jeff Martin
Experienced User
Username: jeff_r_1

Post Number: 124
Registered: 07-2018
Posted on Monday, 24 August, 2020 - 15:56:   Edit PostDelete PostView Post/Check IP

I would stay away from that mechanic, if the engine was so worn where so much oil was getting on the plugs to cause the engine to stop, it wouldn't run at all.
Weather that oil was coming from the top or bottom.
What engine is this, 6 or 8 ?

Just from experience and if it consistently stops after the same time, all the time, I would suspect a faulty ignition coil, especially if it's an old coil, or even more so if it's the original one.

Given the fact that it runs perfectly and the problem surfaces after a 1/2 hour, I would start with ignition coil. Pending on how old the coil is.
Simple enough to replace with a known working coil before replacing the valve seals, which is sort of a big job.
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Patrick Lockyer.
Grand Master
Username: pat_lockyer

Post Number: 2357
Registered: 09-2004
Posted on Monday, 24 August, 2020 - 16:32:   Edit PostDelete PostView Post/Check IP

Being a V8 it could just be the fuel pump failing or filter blockage, engine running weak before stopping will run hot and smoke as one carb runs weak first!
Any miss fire before final stopping?
Just my thoughts.
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ALESSANDRO RAMIREZ GAMEZ
New User
Username: alessandro_rg

Post Number: 3
Registered: 04-2020
Posted on Monday, 24 August, 2020 - 17:51:   Edit PostDelete PostView Post/Check IP

Thanks for quick answers. V8 Silver Cloud from 1960 (sorry I forgot to mention). Car doesnt stop when it gets hot, it simply looses power and smells a bit oil. If I stop it and cool it for about an hour it works properly again. When it happens, the next time I start it again It smokes bad for a minute (like it was expulsating all the oil in the cylinders).
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Jeff Martin
Experienced User
Username: jeff_r_1

Post Number: 125
Registered: 07-2018
Posted on Monday, 24 August, 2020 - 19:57:   Edit PostDelete PostView Post/Check IP

I'd like to see the plugs.
If indeed there is enough oil getting on the plugs to make the engine loose power, one would expect fouling to the point where it would eventually not start at all.
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ALESSANDRO RAMIREZ GAMEZ
New User
Username: alessandro_rg

Post Number: 4
Registered: 04-2020
Posted on Monday, 24 August, 2020 - 21:18:   Edit PostDelete PostView Post/Check IP

Could you please let me know where is the oil breather? Sorry cant find it in the manual.
1960 RR Silver Cloud II
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Hubert Kelly
Frequent User
Username: h_kelly

Post Number: 404
Registered: 03-2012
Posted on Monday, 24 August, 2020 - 21:24:   Edit PostDelete PostView Post/Check IP

By any chance did these symptoms occur after an oil change?. The reason I ask years ago I changed a head gasket on a vw golf used a particular oil which at the time appeared to me to have no viscosity, but I used it as recommended by the motor factors. Anyhow smokey as hell.
I was suspect of the oil, renewed same car was perfect.
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Trevor Pickering
Experienced User
Username: commander1

Post Number: 143
Registered: 06-2012
Posted on Monday, 24 August, 2020 - 21:48:   Edit PostDelete PostView Post/Check IP

The crank case breather goes into the side of the oil filler just below the cap.
Remove it and clean the gauze filter out.
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Geoff Wootton
Grand Master
Username: dounraey

Post Number: 2222
Registered: 05-2012
Posted on Tuesday, 25 August, 2020 - 02:43:   Edit PostDelete PostView Post/Check IP

Hi Alessandro

I note you live in Southern Spain. A beautiful place to live and nice and hot in summer. 30C typical at this time of year, so I'm thinking another possible cause is heat soak. This is where the under bonnet temperature gets high enough to vaporize the petrol in the carburetor float chambers causing the engine to lose power. Intocar sells a kit to prevent it from happening.

I had the same problem when I lived in Florida but in my case replacing a faulty viscous fan coupling cured the problem by producing, as an additional benefit, a better air flow over the engine. It's still a marginal problem on my Shadow as I can get slight misfiring when restarting a hot engine when the ambient temperature is 30C+. This goes away once the cooler petrol is pumped through. RR introduced a plug and tube assembly (Part Number CD1864) to help prevent the heat soak problem on the Shadows.

This is just another thing to check in addition to all the excellent advice above. Another big possibility in my view, as noted above, is the coil.
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gordon le feuvre
Frequent User
Username: triumph

Post Number: 360
Registered: 07-2012
Posted on Tuesday, 25 August, 2020 - 17:37:   Edit PostDelete PostView Post/Check IP

Alessandro, if engine is NOT actually overheating, symtoms are close to coil breaking down. this would be indicated by unburnt fuel collecting in cylinders prior to final stop. When re-started this oil/fuel mix blown out. I had coil fail in similar fashion on 1963 SC111 a couple years back that i was roadtesting.
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ALESSANDRO RAMIREZ GAMEZ
New User
Username: alessandro_rg

Post Number: 5
Registered: 04-2020
Posted on Saturday, 29 August, 2020 - 06:08:   Edit PostDelete PostView Post/Check IP

I really appreciate all your comments and suggestions, thanks a lot. Yes, it is difficult to handle with classics over 36-42 degrees in summer.
Will let you know once the issue is over, thanks again
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michael vass
Frequent User
Username: mikebentleyturbo2

Post Number: 686
Registered: 07-2015
Posted on Saturday, 29 August, 2020 - 18:02:   Edit PostDelete PostView Post/Check IP

I would guess coil, possibly condenser.
Mike
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Mark Aldridge
Frequent User
Username: mark_aldridge

Post Number: 691
Registered: 10-2008
Posted on Sunday, 30 August, 2020 - 03:44:   Edit PostDelete PostView Post/Check IP

Alessandro, If you replace the coil, try to ensure it is vertically mounted , with the terminals at the top. Modern high output coils do not like working on their side or vertically with terminals at the bottom. I have had recent failures on my S1 Bentley and my MG and various articles on Google suggest mounting position may be the cause. Both coils were the same make.
Mark
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Jeff Martin
Experienced User
Username: jeff_r_1

Post Number: 126
Registered: 07-2018
Posted on Sunday, 30 August, 2020 - 08:45:   Edit PostDelete PostView Post/Check IP

Hi Mark
Were those failed coils filled with oil or were they solid resin coils ?
You should be able to place a resin coil in any direction.
Oil filled coils have to be placed with the terminals on top because the oil will eventually leak out.
This of course will defeat it's cooling abilities and cause coil failure.
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Mark Aldridge
Frequent User
Username: mark_aldridge

Post Number: 692
Registered: 10-2008
Posted on Sunday, 30 August, 2020 - 20:58:   Edit PostDelete PostView Post/Check IP

Jeff, The coils were a well known make of high performance oil filled, there was no leakage . They lasted about 5k miles. The original coils were also oil filled,but were changed when electronic ignition was fitted. The original coil on the MG was 40 years old with no problem. I have replaced them with Lucas sports coils, see how long these last ! I keep a spare in the boot.
Mark
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Colin Silver
Experienced User
Username: colsilver

Post Number: 179
Registered: 08-2008
Posted on Saturday, 05 September, 2020 - 13:06:   Edit PostDelete PostView Post/Check IP

ALESSANDRO, you said Yes, it is difficult to handle with classics over 36-42 degrees in summer.
Melbourne can do that and my SC1 was overheating on a family wedding on a hot day and climbing mountanious roads. I had the radiator fixed and with a thermatic fan haven't had a problem a decade on.
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ALESSANDRO RAMIREZ GAMEZ
New User
Username: alessandro_rg

Post Number: 6
Registered: 04-2020
Posted on Thursday, 01 October, 2020 - 19:40:   Edit PostDelete PostView Post/Check IP

Hi everyone, I cleaned and refilled gearbox, filter, and torque converter. I changed the coil and let the oil cap open while driving for 45 minutes. Now i am having two different issues:

1.- Engine runs well but after 45 minutes it starts smoking white a little bit (however its not losing power). Smoke smells like poison, unbreatheable in a close garage. Just to let you know that timing and carburettors were adjusted recently.
2.- Slips during 2-3 upshifts (15mph). It didnt slip before. According to manual: throttle linkage or front band incorrectly adjusted, leak oil in the circuit, sticking control valves, rear clutch plates worn or burned.

Please feel free to share your comments and experience about these two issues, thanks
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ross kowalski
Prolific User
Username: cdfpw

Post Number: 1500
Registered: 11-2015
Posted on Thursday, 01 October, 2020 - 19:53:   Edit PostDelete PostView Post/Check IP

Vacuum modulator
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David Balfour
Frequent User
Username: sidchrome

Post Number: 204
Registered: 02-2009
Posted on Friday, 02 October, 2020 - 00:36:   Edit PostDelete PostView Post/Check IP

Hi Alessandro, Is the white smoke coming from the exhaust pipe, or is it just seem to be rising from under the car?
You have likely inadvertently created an additional fault with the transmission.
When you say, "I cleaned and refilled gearbox, filter, and torque converter", exactly what did you do?
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Robert J. Sprauer
Frequent User
Username: wraithman

Post Number: 648
Registered: 11-2017
Posted on Friday, 02 October, 2020 - 01:36:   Edit PostDelete PostView Post/Check IP

White smoke from the tailpipe is usually associated with coolant in the combustion chamber and you will see the temp gauge move to hot, or if an automatic, the trans fluid is being sucked into the intake manifold due to a faulty vacuum modulator on the transmission.
If you try to drive the car with a bad modulator, you will also experience poor shifting, and continued useage makes the bands and clutch plates in the transmission very unhappy.
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David Balfour
Frequent User
Username: sidchrome

Post Number: 205
Registered: 02-2009
Posted on Friday, 02 October, 2020 - 07:46:   Edit PostDelete PostView Post/Check IP

Alessandro, Is this a stock Silver Cloud 2? If so, there is no vacuum modulator or vacuum of any kind attached to the Hydramatic. There is the throttle linkage and input shaft only. I think the new symptom is not associated with the original issue. In servicing the transmission you have altered the hydraulic performance of the transmission, and it now needs adjustment. I cannot think of any way for either PAS fluid or Transmission fluid from passing to the engine and being combusted. I'm sure if I'm wrong I will be immediately corrected. Therefore the white smoke would likely be coolant. Are the S.U. dashpots still full of oil btw? They are the only other source of fluid on the engine I can think of. Maybe someone can say if there is a potential leak path. In any case check coolant, dash post, and PAS just to be sure.
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David Balfour
Frequent User
Username: sidchrome

Post Number: 206
Registered: 02-2009
Posted on Friday, 02 October, 2020 - 07:48:   Edit PostDelete PostView Post/Check IP

That is check their levels!
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Jeff Martin
Experienced User
Username: jeff_r_1

Post Number: 142
Registered: 07-2018
Posted on Friday, 02 October, 2020 - 09:42:   Edit PostDelete PostView Post/Check IP

Why did you leave the oil cap open for 45 minutes while driving ????

The white smoke is oil now burning off the exhaust manifold(s) ?

You don't say if it's coming from the engine bay or specifically from the exhaust pipe only.
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Mark Aldridge
Frequent User
Username: mark_aldridge

Post Number: 698
Registered: 10-2008
Posted on Friday, 02 October, 2020 - 20:18:   Edit PostDelete PostView Post/Check IP

Alessandro, David is correct. What transmission fluid have you put in the gearbox.

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