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View Full Version : Spitfire Compression Test - Spit 1500



pjsmetana
06-21-2009, 05:56 PM
https://i83.photobucket.com/albums/j293/pjsmetana/P1020126.jpg

https://i83.photobucket.com/albums/j293/pjsmetana/P1020127.jpg

https://i83.photobucket.com/albums/j293/pjsmetana/P1020128.jpg

https://i83.photobucket.com/albums/j293/pjsmetana/P1020131.jpg

https://i83.photobucket.com/albums/j293/pjsmetana/P1020132.jpg

As you can see... 100psi, 70psi, 95psi, 100psi... and the pic of the plug is from the one that was the lowest (the others were perfect). Each check was 8 revolutions (but leveled off at 4).

Since only 1 was low, its not the head gasket, and since I'm blowing oil out of my dipstick hole, I can only assume its my rings and not valves. I didn't do the 30wt oil-in-chamber check as my battery was running low, and that would only confirm/deny the rings vs valves.


So what now? Is this still OK enough to drive to the car show in 2 weeks or will I likely blow my head gasket or worse?

Andrew Mace
06-21-2009, 07:17 PM
I'd do the oil-in-chamber check to be more sure, but you're probably right that it's rings. Probably ok to keep driving, so long as you keep your eye on oil level and pressure, etc. But it's probably overhaul time. (Not even that hard to do while the engine remains in the car, so long as you don't require a rebore!)

poolboy
06-21-2009, 07:42 PM
Having just one cylinder low causes me to think that it just might be a valve problem, either one stuck and not closing or one burned and cannot seal.
A check with a Vacuum Gauge could be of great assitance in knowing what to expect before a tear down.
I had a low compression reading on one of the cylinders when I got my TR6, about 25 #'s lower than the rest, and some spirited driving with detergent added to the gas cleared that up in a few weeks. The valve was apparently prevented from closing due to a carbon buildup. Here's a link for interpreting Vacuum Gauge readingss. You'll see how a valve problem can be diagnosed. As for the oil blowing up the dipstick, yeah it could be blowby or just a problem with your crankcase/ valve cover ventillation; been there, too.
https://www.users.bigpond.com/ergoff/vac1.htm

pjsmetana
06-21-2009, 08:15 PM
I'd do the oil-in-chamber check to be more sure, but you're probably right that it's rings. Probably ok to keep driving, so long as you keep your eye on oil level and pressure, etc. But it's probably overhaul time. (Not even that hard to do while the engine remains in the car, so long as you don't require a rebore!)

When I get some regular non synthetic 30wt I'll try it (every bit of oil in my garage is Amsoil... even the drops on the floor), but I'm pretty sure I'll get the results of my guess. I'm not burning any oil though... not even on a cold start.

I used to use ATF in the carbs when trying to unstick a valve or ring with the old aircooled bugs... think this is worth a shot on this engine?


Having just one cylinder low causes me to think that it just might be a valve problem, either one stuck and not closing or one burned and cannot seal.
A check with a Vacuum Gauge could be of great assitance in knowing what to expect before a tear down.
I had a low compression reading on one of the cylinders when I got my TR6, about 25 #'s lower than the rest, and some spirited driving with detergent added to the gas cleared that up in a few weeks. The valve was apparently prevented from closing due to a carbon buildup. Here's a link for interpreting Vacuum Gauge readingss. You'll see how a valve problem can be diagnosed. As for the oil blowing up the dipstick, yeah it could be blowby or just a problem with your crankcase/ valve cover ventillation; been there, too.

I tried the spirited driving today with no change. I don't have any detergent, so what should I get?

I don't have a vacuum gauge either, so a link to what kind I should get would be quite helpful.

Can I replace rings on this engine without pulling it? I'm thinking maybe so if a ring compressor will fit flush from the under side and clear the crank. I've only ever done rings from the top.

As for crankcase ventilation... Its clean and clear. I had the rocker cover off when I repainted it, replaced the hose, and have a new PVC tube into my new K&N Air cleaner. It works just fine.

poolboy
06-21-2009, 08:58 PM
Chemtool B-12 is a good detergent as is Techron, but don't expect "overnight " results. It took a couple of weeks driving some every day to break-up the deposit I had. You can find the gas detergents at places like Advanced Auto, Autozone, O'Rieleys and Walmart.
The Vacuum Gauge at the first 3 I mentioned for about 30 dollars.
You can push the pistons out of the top, like you did in the past, after you drop the pan and take the rods loose from the crank.

bgbassplyr
06-21-2009, 09:00 PM
"Can I replace rings on this engine without pulling it? I'm thinking maybe so if a ring compressor will fit flush from the under side and clear the crank. I've only ever done rings from the top. "

And thats the only way you will ever do it.

Pull head and pan, remove the rod cap(s), push the piston(s) out of the cylinder. Don't mix up the rod caps.
Check the top of the cylinder for ring wear. This will be a lip at the top of the cylinder. If there is one, you must first remove it (there is a tool for doing this, not expensive) or the piston rings will hang on the lip.
Clean the piston, esp the ring lands. Install new rings with the gaps offset from one another. Clean up the cylinder with a hone, being sure to cover the crank journals to protect them from debris caused by the honing. Blow out with compressed air and wipe the cylinder to remove what ever the air didn't remove. Apply oil or assembly lube to the pistons, rings, and cylinder bore. Reinstall piston using a ring compressor.
You might want to replace the rod bearings while you're there. Mains too, if you've got the time.
Reassembly from here is the reverse blah, blah, blah.

I'd look at the valves first though, as they(it) can can cause the same type of problems that you are experiencing. You might try misting some water into the carbs using a spray bottle while the engine is running. This will usually knock carbon build up off of the valves and piston tops.
Hope this helps.

pjsmetana
06-22-2009, 05:50 AM
You might try misting some water into the carbs using a spray bottle while the engine is running. This will usually knock carbon build up off of the valves and piston tops.
Hope this helps.

Water eh? This is new to me. Is it at idle or when goosing it like the old ATF trick? (Again, will the old ATF trick even work on these?)

tdskip
06-22-2009, 09:01 AM
Sorry if I missed this - but have you adjusted the valves recently?

RonMacPherson
06-22-2009, 11:50 AM
Ok, after adjusting the valves. PLEASE remove ALL spark plugs when performing a compression test.....


Good idea to remove an ignition supply wire(primary lead to the coil). I also recommend blocking open the throttle. Then crank the engine 5-6 cycles on each cylinder......

jjw
06-22-2009, 02:06 PM
Wow... the "water trick"... been awhile since I've heard of that being used. Way back when, a mechanic taught me how to do that with my old college beater car, that was always carbon fouling the plugs... just use to pour water down the carb intake while idling... just not too much too fast or the engine would stall. Blip the throttle a few times to clear things out, and done. Made the plugs squeaky clean...

TR3driver
06-22-2009, 02:18 PM
But let's not forget that 70 psi on #2. That's not carbon fouling; that's a piston or valve that isn't sealing. Combined with the blowing oil, it's almost certainly a piston problem.

To answer the original question, probably it will be OK to drive it to the car show that way. If the piston or cylinder wall are going to get damaged, most likely they already are damaged.

But it is at least possible that you are looking at a broken piston, which means there are pieces that might get loose into the crankcase and make a significantly worse mess than you have now. So the question you have to ask yourself is "Do I feel lucky?".

pjsmetana
06-22-2009, 04:41 PM
So the question you have to ask yourself is "Do I feel lucky?".

Indeed I do!

So this Water Trick... Technique, mist or pour SLOWLY? And when, Idle, Mid RPM, Goosed?

DrEntropy
06-22-2009, 05:05 PM
Mist at RPM. 3K and introduce it. Be prepared to "goose" the throttle as you do. Don't get goofy either... a few squirts and go to the other throat. Then drive it and check things again.

bgbassplyr
06-22-2009, 06:40 PM
ISTR that back in the middle 50's there was a water injection system the hot rodders used for more power when drag racing. Only for shot bursts, not full time. Made a nice white cloud out the tail pipe, too.

3798j
06-22-2009, 07:07 PM
And in 1962, Oldsmobile introduced the F-85 Jetfire. A 215 CI aluminum turbocharged V8 with a water/alcohol "injection" system that allowed a 10.25:1 CR.
https://i490.photobucket.com/albums/rr268/3798j/1962-1963-oldsmobile-f85-jetfire-1.jpg

TR3driver
06-22-2009, 08:01 PM
Water injection has been around much longer than that, at least since the 30's. WWII aircraft used it for more power on available fuel. You see a lot of it at tractor pulls and so on, too (it even works for diesels). For example, the article at https://www.dieselpowermag.com/features/trucks/0607dp_diesel_smoker_tractor_pulling/puller_stats.html talks about using several gallons of water in just a 12 second run.

Somewhat amusing article at https://www.rbracing-rsr.com/waterinjection.html with links to some of the papers done way back in the 40's.

BTW, some may not know, that all-aluminum V8 (which was also used by Buick and Pontiac, tho without the supercharging & water injection) is the direct ancestor of the original engine in the Triumph TR8. GM didn't have very good luck with it (kind of small for those giant full-size cars, and people frequently overlooked refilling the "power fluid") and so sold the design & tooling to Rover back when. Rover has been developing it all these years, and just finally halted production just a few years ago now.

jjw
06-22-2009, 09:30 PM
BTW, some may not know, that all-aluminum V8 (which was also used by Buick and Pontiac, tho without the supercharging & water injection) is the direct ancestor of the original engine in the Triumph TR8. GM didn't have very good luck with it (kind of small for those giant full-size cars, and people frequently overlooked refilling the "power fluid")

...and possibly of interest... The biggest problem GM had with that engine was cost... it actually sold well, but the scrap costs caused by casting issues in block production were high. Also, in service, corrosion problems cropped up due to reactions between the antifreeze formulations of the day and the aluminum block / heads... A lesson that British Leyland and Stag owners re-learned years later with Triumph's internally developed V8... :smile:

TR3driver
06-22-2009, 10:04 PM
Also, in service, corrosion problems cropped up due to reactions between the antifreeze formulations of the day and the aluminum block / heads... A lesson that British Leyland and Stag owners re-learned years later with Triumph's internally developed V8... :smile:
Not so much the formulations available IMO, but the need to replace them every few years, which most Americans ignored until it was too late. Even TR3s have aluminum bolted to cast iron, which will corrode badly if the antifreeze isn't kept changed.
https://i258.photobucket.com/albums/hh260/TR3driver/DSCF0013.jpg

pjsmetana
06-24-2009, 02:55 PM
I was just thinking (harmful to my health, I know)...

Is it possible that my motor oil is too thin?

It wasn't leaking or anything till I changed to Amsoil 5w30 XL. Only reason I used it is because I couldn't get a definitive answer on the weight of the oil to use, and I had a full case of it as a mistake order for my Honda (uses Amsoil 5w20 XL).

Also, I haven't had the time to try the water trick yet, but when I try it, I'll post results.

DNK
06-24-2009, 02:56 PM
UH, Yea.

pjsmetana
06-24-2009, 03:01 PM
UH, Yea.

Ok then, what weight should I change to?

I have straight 30 weight in Tranny, OD, and the Dif...

DNK
06-24-2009, 03:10 PM
Pete, believe me when I say among the folks on this forum I am FAR from the wizard.
I don't know about Spits,but most of the 6's use 20/50

I might be talkin out of my blow hole on this...

pjsmetana
06-24-2009, 03:19 PM
I called Amsoil, I got this info back;

<span style="font-weight: bold"><span style="font-style: italic">LUBRICANTS &amp; FLUIDS
Engine Oil
Grade 1......SJ
Synthetic 5W-40 European Engine Oil
SAE 10W-40 Synthetic High Performance Motor Oil
SAE 10W-40 XL Synthetic Motor Oil
-4 to 61F......10W-30
Above 32F......20W-40, 20W-50
Above 14F......15W-40, 15W-50
Above -4F......10W-40, 10W-50
Below 14F......5W-20, 5W-30, 5W-40
Manual Transmission,.....GL-4
Below 0C......80W
Synthetic Manual Transmission and Transaxle Gear Lube 75W-90
Manual Transmission,.....GL-4
90
Synthetic Manual Transmission and Transaxle Gear Lube 75W-90
Differential, Rear .....GL-4
Below 0C......80W
Synthetic Manual Transmission and Transaxle Gear Lube 75W-90
Differential, Rear .....GL-4
All Temps......90
Synthetic Manual Transmission and Transaxle Gear Lube 75W-90
Fluids
Brake Fluid.....HB
Series 500 High Performance DOT 3 Brake Fluid
Clutch Fluid.....HB
Series 500 High Performance DOT 3 Brake Fluid


CAPACITIES
Engine, without filter..........4.2 quarts[1]
Cooling System, Initial Fill..........4.8 quarts
AMSOIL Antifreeze and Engine Coolant

Manual Transmission, W/O OD..........1.7 pints
Manual Transmission, W/ OD..........3.2 pints
Differential, Rear..........1.3 pints</span></span>

So I guess I should do a full fluid change as well. This still dont convince me that 5w30 is too light, as its listed in the Cold Temps, but Since I only drive on nice hot days I'll still change it, tranny too it seems.

DNK
06-24-2009, 03:21 PM
I lived in MD. You should be using a Humid weather oil.

TR3driver
06-24-2009, 05:07 PM
Pete, we can debate optimum oil viscosity and formulation until we are old and gray (as proven by the on-going debate over just one motor oil component, ZDDP). But the plain truth is that, if it did make a difference, a compression reading that low indicates that the damage has already been done. You have a big, gaping hole (in terms of normal cylinder/ring clearance) somewhere. Switching to a heavier oil at this point may make the reading a bit higher, but won't eliminate the damage or make the engine run any better.

Same goes for carbon/deposit buildup in the cylinder. Adding water ain't a gonna help with the compression.

Don't have any photos to share, but my 59 TR3A was in a similar condition when I bought it. The rings in one cylinder (think it was #3 but that was a long time ago) had rusted to the cylinder wall and left big pits in it. Apparently when someone got the engine running, both compression rings caught on the rust pits and broke ... they came out in pieces. I had already driven the car several months before I found time to investigate why it had so much blow-by ... lacking resources to deal with the problem, I just stuffed a new set of rings in and buttoned it back up, complete with extreme cylinder wall wear and rust pits. Drove it that way almost every day for about 5 years, too.

Eventually another engine came my way and I put that in; never did look to see how those rings fared. But the new rings did help reduce the blow-by and it didn't use an unreasonable amount of oil.

tdskip
06-24-2009, 05:25 PM
I lived in MD. You should be using a Humid weather oil.

LOL Don. Can I assume you use a special wet formulation? Lots of people down here us special silicon enhancements...

Mark Jones
06-25-2009, 06:37 AM
The owners manual for a Spitfire says 20W50, just like most other Triumphs. Even my TR7 calls for 20W50.

poolboy
06-25-2009, 08:28 AM
I think by using an oil lighter than 20w-50 you can usually expect 2 things.
You'll use more oil and your oil pressure will be lower; that is unless you are driving around in the Great White North.

RonMacPherson
06-25-2009, 11:55 AM
If you are wondering why the Amsoil folks recommend European oil... ZDDP. which is found in the European oil. Good ole' US EPA got the American oil formulators to change their additive package reducing, or deleting ZDDP(which is a very inexpensive(on the scale the oil refiners use it) antiwear additive. It also can contaminate catalytic convertors...

European oil manufactures adhere to their auto manufacturers request and kept ZDDP oil in their oil..


But, it is not that easy to come by over here in the US of A.

jjw
06-25-2009, 12:14 PM
I don't think a higher viscosity oil is going to do anything to address the problems you have, but I know for sure that if I ran a 5w30 synthetic in any of my British cars, most of it would be lining the engine bay and/or puddled on the floor in short order... :smile:

tdskip
06-25-2009, 01:07 PM
Wait a second - wasn't this thread about compression figures? As stated above oil viscosity isn't going to change your compression ratio. Oil pressure for sure, but not compression.

DNK
06-25-2009, 01:49 PM
When has this group ever known to stay on task?

tdskip
06-25-2009, 02:09 PM
Hi Don - yeah I was just trying

Oh look, a squirrel!

pjsmetana
06-25-2009, 03:59 PM
Oh look, a squirrel!


Cool, unless hes dragging up the old ZDDP discussion too. lol

pjsmetana
06-27-2009, 06:48 PM
So this Water Trick...

I did this as Doc described. ~3k RPM with a spray bottle. 'Bout 2 cups of water per barrel, then pumped the accelerator to see if it would smoke at all. Around the time I finished the 2nd barrel the smoke started going away when pumping. I then put my filter back on, hopped into the drivers seat, and floored it all the way to the auto parts store.


Chemtool B-12 is a good detergent as is Techron...

I got a quart of cheep-o 30wt oil and a bottle of the Techron, as I didnt see any Chemtool B-12 anything. I put half the Techron bottle in the tank and then ran her hard around town for about 20 mins. By the time I got home I felt like the engine was running a bit smoother. When I pulled into my garage I noticed I was barely leaking any oil at all.

I'll probably run the compression test again tomorrow.



So the question you have to ask yourself is "Do I feel lucky?".

Indeed I do!


I feel like tomorrows drive will include stopping to get a lotto ticket!!! We'll see...