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Spitfire Engine or Gas additives to Spitfire?

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desmo900rider

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Is there anyone here who has had good or bad experiance with any types of oil or gas additives? I have a friend who is a Land Rover mechanic that claims Marvins Mystery Oil, a gas additive, works really well, I used it on my Discovery when it needed a valve job per his recomendation and it seemed to work really well...I also have a friend who swears by Motor Honey in his oil, says it helps to condition valve seals, stil reading up on that...any long term risk to trying these types of products in my Spit? Anything to stay away from?

I am also trying to determine if I have a head gasket leak, and have found some products out there that claim to seal small leaks in both head gaskets and engine blocks...not sure if there is harm in using those though...if the head gasket needs to be replaced, I would like to either wait until I come into some money to have the shop do it, probably $500-600, or get the courage/time to do it myself...it seems like a hefty project though for a newbie mechanic...


Thoughts?

Mike
 
Personally, I don't think Marvel Mystery Oil will do any harm, and it might help a bit as an "upper cylinder lubricant/fuel additive." But most all of the "engine rebuild in a can" type of additives are pretty much useless (although STP is great to use as an assembly lubricant). Even if Motor Honey does help "condition valve seals," Spitfires don't HAVE valve seals unless someone has gone to some trouble to add them.

As for something to seal small leaks, I always worry that the product might end up sealing some other passage that should NOT get sealed up! /ubbthreads/images/graemlins/eek.gif

If a head gasket does need to be replaced, I would absolutely NOT count on any miracle additive to put off the inevitable; much better to park the car and save your money until it can be fixed. If nothing else is wrong, I shouldn't think it should cost more than $300 or so at a fairly expensive shop to do the job. But, with only a relatively few special tools (mostly a good torque wrench) and a good workshop manual (and local club members and the rest of us here on the Forum), changing a head gasket is not beyond even a "newbie" mechanic's skills.
 
Hi Mike,

I agree with Andy in most respects. Many of the additives are not worth the extra expense. Some seem to do more harm than good in the long run, might only offer a very temporary solution, at best.

I will make an exception for Bar's Radiator Stop Leak.

I have personally used it with good success in several cars that were otherwise impossible to keep the coolant out of the sump. (Such as a friend's Pontiac with a 2.1L engine that's notorious for this and overheating problems in general... Bars has been in there and done the job for 4-5 years now... This was after extensive work on a warped and cracked cyl. head by a dealer and my own efforts replacing the water pump, installing a new thermostat, new hoses and clamps, etc., etc.)

BTW, Bars has been OEM specified by GM for some years for use in all-aluminum or aluminum head engines in Cadillac and others. It's right in the factory service manual.

Your previous questions about white "smoke" and recently noticing a puff of it when the car was first started in the morning *really* lead me to believe you have a slow, seeping leak in the head gasket.

You say there's little or no indication the coolant is getting into the sump and mixing with the oil, which likely means it's only getting into one or more cylinders and the head gasket is sealing pretty well otherwise.

I'd also try to find out why the coolant header or overflow tank is dry. It shouldn't be. It should be fuller when the engine is hot (and the coolant expands out of the system into the tank) and drop to about one third or half-full when the engine is cold (and coolant is drawn back into the system, rather than air).

Even if the radiator itself appears full when cold, if that header/overflow tank is empty, some air is probably getting into the cooling system. When that happens, steam is created, leading to more leaks and hot spots, and can do damage to the engine pretty quickly. In fact, steam or hot spots might be the cause of a small head gasket leak, or could be the result of one. Plus, a leaky head gasket might seal when warmed up, only to leak again when the engine is cooling down. Or, it could be that when warmed up and running hot exhaust gases are pushing past the head gasket into the cooling system, compounding the problem.

If the overflow/header tank level keeps dropping, especially so dramatically that it's dry in a short time, there is a problem that needs addressing. If you don't see any coolant on the ground, it's gotta be going into the engine. If not in the sump, it has to be going into a cylinder and then out the tail pipe. If you half-fill the overflow/header tank with a pint or two of coolant and then find it dry after a day or two or three, *a lot* of coolant is finding it's way through the engine.

But, before resorting to additives, try torquing the cylinder head nuts to see if any are loose and if that might pull the head down better to stop a leak. (The head also might be warped and impossible to pull down adequately, as a result of localized overheating). I don't have a manual in front of me to check the torque specs for Spitfire cylinder head nuts and the correct tightening sequence. Hopefully you have a manual for reference and a good torque wrench to use, or can borrow one.

If re-torquing the head doesn't help, Bars might help temporarily and might be a good diagnostic tool, although I'd not necessarily consider it a long-term solution. If it's leaking the head gasket ultimately should be replaced, as Andy said. But, if you add some Bars to the radiator, the white "smoke" stops and the overflow/header tank keeps some level of coolant in it, you have certainly identified the problem as a head gasket leaking a little coolant into one or more cylinders.

Adding Bars might also not help, in which case the head gasket is just leaking too much and has to be replaced before the car is driven much.
 
I have used Marvel Mystery Oil in the gas for years. Also use it in the dashpots.
The oil additive that I have used and like is Lucas Oil Stabilizer. Most of the shops I call on also use it.
I have tried Redline Water Wetter, but the jury is still out. I've heard some people claim good results, but I haven't seen it yet.
 
Quite the demo.
Really makes me wonder about all the Gas Additives intended to help our LBC's with unleaded gas....
 
Two cans of motor honey stopped that annoying cloud of blue smoke from following me around in a Dodge Colt back in the day... at least until I sold it /ubbthreads/images/graemlins/devilgrin.gif
 
[ QUOTE ]
...
Really makes me wonder about all the Gas Additives intended to help our LBC's with unleaded gas....

[/ QUOTE ]Yep, like the two cans of some no-name lead substitute that came in the trunk of my current Herald 1200 when I bought it four years ago. I'm relatively sure the engine has never been touched, so no sort of "conversion" would have been done to the head. I've put around 25,000 miles on the car in those four years, and those two cans of whatever are still sitting in the garage unused. Engine is still fine...as good or better than when I got it (maybe because the previous owner put 700 miles on the car in 13 years, and I put over 3000 miles on it within a month of my purchase).
 
[ QUOTE ]
Two cans of motor honey stopped that annoying cloud of blue smoke from following me around in a Dodge Colt back in the day... at least until I sold it /ubbthreads/images/graemlins/devilgrin.gif

[/ QUOTE ]

Jim, here I had all these good thoughts about you for bringing me to this forum! /ubbthreads/images/graemlins/grin.gif
 
[ QUOTE ]
[ QUOTE ]
Two cans of motor honey stopped that annoying cloud of blue smoke from following me around in a Dodge Colt back in the day... at least until I sold it /ubbthreads/images/graemlins/devilgrin.gif

[/ QUOTE ]

Jim, here I had all these good thoughts about you for bringing me to this forum! /ubbthreads/images/graemlins/grin.gif

[/ QUOTE ]

The statute of limitations have LONG expired on that one and I got _plenty_ of karmic payback for that shady caper /ubbthreads/images/graemlins/smile.gif
 
[ QUOTE ]
The Marvel Mystery Oil does make the exhaust smell nice. :>)

[/ QUOTE ]

If you like the smell of Marvel, better check out https://www.liquidhorsepower.com/fuel-fragrances.php

Or switch to Castrol R in the sump. It smells pretty darn good too! (Best to do a fresh rebuild of the engine first, though, if switching from a mineral or synthetic motor oil.)

/ubbthreads/images/graemlins/cheers.gif
 
[ QUOTE ]
Here's some interesting info on using unleaded and valve seat rescession(sp?)https://www.canleyclassics.com/triumphmuseum.asp?article=esso.xml

[/ QUOTE ]

Yeah, I think the issue of valve seat recession is vastly overblown. It does occur, more on some cars than others. The 4 cylinder TR2/3/4 head is *not* very prone to recession. I had a metallurgist explain it to me, that the alloy used to cast the heads was pretty resistant to recession. Very hard driving and high engine temps, such as on a race track, might cause some problems, but more likely the pre-unleaded valve guides and the valves themselves will be damaged before any recession occurs. Other makes and models may act differently. This is by no means a universal observation.

Somewhere I saw an extensive and careful comparison of the various "unleaded" additives, that showed some provided a little benefit, but others didn't. Maybe a Google search would turn something up.

/ubbthreads/images/graemlins/cheers.gif
 
[ QUOTE ]
I have tried Redline Water Wetter, but the jury is still out. I've heard some people claim good results, but I haven't seen it yet.

[/ QUOTE ]

Water Wetter helps a little in a normal cooling system, when anti-freeze is part of the mix. I think its more effective in water-only cooling systems, such as is required on race tracks.

There are some other cooling additives available, as well. DEI and Royal Purple each now offer one or two. DEI claims 30 degress F temp reduction with their "Radiator Relief", but the stuff is pricey.

These aren't a final solution for overheating problems, which should be sorted out and fixed properly, but might help in extreme situations or with particularly stubborn cars (like the Pontiac I previously mentioned).

/ubbthreads/images/graemlins/cheers.gif
 
Personally, I like to keep a mixture of "Seafoam" in my gas tank. The engine has run MUCH smoother since I started using it. It also acts as a fuel stabilizer to help keep the fuel fresh.

Don
 
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