MGB-GT Starting tune up of my 70 BGT

[RickB]

I started the tune up today between the rain drops.

First things out = an old set of NGK plugs.
Very black & nasty, but gap right on at .025
Don't know what I was thinking but the new set I put in had a gap of .030 and I just left them like that. Is that going to cause a problem?

I have 6 quarts of 20W-50 here and will have a new filter on Monday. Also coming Monday are a new cap & rotor along with a set of plug wires. I figure none of that stuff has been replaced in 20 years, the car runs OK as-is and performance is pretty good but fuel economy is terrible.

Next I'll likely get a pair of K&N air filters and clean / tune the carbs. The color of the plugs indicates the carbs are set a wee bit rich /bcforum/images/%%GRAEMLIN_URL%%/wink.gif

 

[tdskip]

Don't know what I was thinking but the new set I put in had a gap of .030 and I just left them like that. Is that going to cause a problem?

I'd get a couple other opinions, but I don't think this will have harmed anything.

Next I'll likely get a pair of K&N air filters and clean / tune the carbs. The color of the plugs indicates the carbs are set a wee bit rich /bcforum/images/%%GRAEMLIN_URL%%/wink.gif

You'll like the K&N filters - I found them to make a nice difference on my car.

 

[Bugeye58]

Rick, provided the rest of the ignition system is up to snuff, a gap of .030" should be no problem. Hopefully, the black deposits on the old plugs was fluffy soot, not oily residue.
I second Toms' comments on the K&N's. They are all I run on my cars, offering excellent filtration with the added benefit of being washable.
Jeff

 

[davester]

I was thinking of going to K&Ns a few years ago, but the only valid testing data I found on them showed that they let through vastly more dirt than regular paper filters, and even more if they are not kept clean and oiled. I would rather have my engine last longer than gain a marginal amount of power.

 

[RickB]

Dave, I wondered about that too - then I saw pics on Bob Muenchausen's site.
https://www.cibolas7.net/4436.html

He lives in Idaho and it can get really dusty there, I've been there several times. Here is a little quote from him:

<div class="ubbcode-block"><div class="ubbcode-header">Quote:]BOB:
Here is an untouched photo of the mouth of one of my SUs taken immediately after removal of my K&Ns after a 14 month term of service. The K&Ns used were at least 10 yrs old, having had only normal maintenance as prescribed by K&N when using their products.[/QUOTE]

<div class="ubbcode-block"><div class="ubbcode-header">Quote:]BOB:
The "unvarnished" truth! I don't sell 'em, I am not even sure that they clean as well as some modern alternatives, such as those offered by Amsoil, but this is a sample of my luck, and I live in the filth capital of Idaho, land of constant earth moving and development.[/QUOTE]

Hap Waldrop uses them & seems to endorse their use pretty strongly, and many other well respected members here use them too.

When I removed my cans the other day what I saw in the throats of my SU's was not nearly as clean as Bob's picture.
I know the filters in there now are not doing a great job.

BTW I have ordered a pair and they are coming to me for $52 shipped. Got them from Full Line Exhaust: fle-online.com (free shipping for orders over $50)

I almost ordered from Speedwell then I saw that although they offer free shipping there was an almost $11 handling fee. That just turned me off - I think that if you are saying "free shipping" it's a bit rude to tack on a big handling charge. Just MHO.

 

[RickB]

Jeff, yes it was fluffy and not oily.
I really don't know how long those plugs have been in there, but I have a feeling it's been a long time. I know the PO had the car in his garage for somewhere between 14 - 20 years.
So, not a lot of mileage but a lot of sitting around time. He would just start it up & move it a little once in a while.

It started and ran fine with the new plugs.

 

[davester]

Re: K&N. Being a scientist, pictures don't do it for me. I like cold, hard, unbiased data. Hence: https://home.stny.rr.com/jbplock/ISO5011/SPICER.htm

 

[RickB]

Thanks Dave, I feel it's necessary to point out a couple things.

First, the one in the test you mention, a filter for a diesel truck.

Next, the filters I'm getting:

These are heartily endorsed by members here, who say they noted real world improvement when using these.

I think the application is the main difference. A set of two filters that fit right over the stacks on SU carbs is pretty handy - what other options are there?

A pair of pancake filters, a set of foam element chrome jobbies? These are options, as well as the option of simply putting more paper filters in the original cans.

Does an MG engine benefit from higher cfm air flow? Most here agree that it does.
I'm in the camp with those who think the K&N filters that fit right on the original stacks will work pretty well. I suppose I will see since mine will arrive within a week. /bcforum/images/%%GRAEMLIN_URL%%/wink.gif

 

[RickB]

So today it was sitting there idling just fine, I had done the modification to the stock velocity stacks and shined them up with some fine steel wool and then cleaned and installed them.
I used about a can of carb cleaner on the outsides of the SU's and a half a can inside. I found my front carb choke was stuck, worked it loose.

It was idling just fine and I walked up to my porch for something when it just died.
No cough, no splutter - just died!

So I start checking, fuel side was good.
Checked spark, key on & opening the points produced spark.
Looked at contacts on the cap - hmmm... looked white.
Scraped with the end of the screwdriver & the white scale popped off. Put it back together & it started up just fine.

New cap & rotor will be here tomorrow.

 

[jlaird]

Oh Rick, no cheep way to get the job done. Ask me I know.

 

[RickB]

Yes, I follow your progress Jack.
Its instructive!

Actually I ordered the other parts several days ago, but I was able to get plugs & carb cleaner right away so that's where I started. Man this thing really needs an oil change! Filter should also be here today!

 

[RickB]

I let Bob M. know I was quoting from his site, (yes I did invite him to join) - he came and read this thread (and I'm sure some others) and had a comment:

<div class="ubbcode-block"><div class="ubbcode-header">Quote:]
Bob Muenchausen:
One comment you might want to make (or quote this one) on the second issue (filtering capability of K&Ns) ~ the photo simply shows that they do at least as credible a job of keeping out the worst of the road flotsam as do the ordinary paper filters and more than some of the foam ones. It was aimed at those skeptics who cannot believe the "hype" about an "expensive" aftermarket air filter made out of some cheezy gauze. As I said on my site, there may well be better products at filtering down to .0005 microns or perhaps the molecular level out there (then we are believing someone else's "hype") but at least a K&N filter does demonstrably less harm than no filter at all, and no worse than most paper filters, which the majority still sees fit to use and the majority of manufacturers continue to install as OE.

I am a firm believer in empirical evidence gathered by actual use, and I offered up my photo simply to prove to the gross naysayers that their worst fears are often unwarranted. There is a lot of Cosmic BS associated with "performance" equipment, and I figured that a look at an actual experience couldn't hurt anyone truly interested in what actually happens. It doesn't mean you can do/find better. But in my experience with cars over the last 45 yrs, I have also been impressed by the ages old wisdom that you do not get something for nothing ~ and by that, I mean that the stronger you filter, the less likely you are to have a similar air flow. That, and I don't expect my engine to last forever. However, the almost twenty years this particular rebuild has been on the road as a daily driver using K&Ns and maintaining oil pressure and compression, has to be worth something in a debate like this. But then, again, that is only empirical evidence, and not laboratory evidence. Sometimes field science betrays hard science.
[/QUOTE]

 

[RickB]

New cap, rotor & wires in at lunch.
Went for a little drive, definitely more vroom vroom.

The idle increased to 1500 after new stuff. Turned it down to about 950.

So how good is the additive for unleaded gas? The stuff that says it's good for 320 gallons of gas, comes in a quart container & you put 1 oz in each 10 gallons?

 

[RickB]

mmmm mmm... 4 qts of Valvoline 20W-50 and one quart Castrol 20W-50 Motorcycle oil and a new filter!

Leaned up the carbs by a couple flats, running smooth & powerful now! /bcforum/images/%%GRAEMLIN_URL%%/wink.gif

Tomorrow morning will tell the tale of course.

Got Marvel Mystery Oil in my dashpots and everything is fine!

 

[RickB]

There's nothing like a freezing cold morning to show you that you leaned your carbs too much. I'll adjust them a bit richer at lunchtime today, it was funny how pulling out the choke just a little gave me so much more power this morning!

Otherwise she's running like a top now! I feel so much better getting that old oil & filter out, that certainly will help!

Has anyone else here heard about the 20W-50 Motorcycle oil thing? Apparently it has more zinc in it among other things and that's good for these old girls.

 

[RonMacPherson]

I use Yamalube in my 6. Also look at the motorcycle oils at the chain stores(checker, etc.) Look on the back of the bottle to see which API grade it is. If it's before SJ or SI good. Sorry can't remember which right now, first cuppa coffee going down. So compare the rating on a bottle of Yamaha oil to that in the chain stores. Might save a little money at the chain stores, my Yamalube is about 4 a quart.

 

[RickB]

Seems to be the going price - $3.50 - $4.00 / quart Valvoline, Castrol, didn't seem to matter much. I'll look at the API grade next time.

 

[davester]

Has anyone else here heard about the 20W-50 Motorcycle oil thing? Apparently it has more zinc in it among other things and that's good for these old girls.

Never heard of such a thing. How do we tell that this is based on reality rather than being an old wives tale? Ditto for the Marvel Mystery Oil (which reeeeally sounds like an old wives tale.

Color me skeptical.

 

[Keoke]

Has anyone else here heard about the 20W-50 Motorcycle oil thing? Apparently it has more zinc in it among other things and that's good for these old girls.

Never heard of such a thing. How do we tell that this is based on reality rather than being an old wives tale? Ditto for the Marvel Mystery Oil (which reeeeally sounds like an old wives tale.

Color me skeptical.

Well it is true:
Simply because Motorcycles do not have catalytic converters and consequently their oil has not been altered in ZDDP content. Similarly, diesel powered cars lack the coverters also and enjoy the same benifit in their motor oil.---Keoke

 

[Keoke]

Re: K&N. Being a scientist, pictures don't do it for me. I like cold, hard, unbiased data. Hence: https://home.stny.rr.com/jbplock/ISO5011/SPICER.htm

Well Davester, I do not see anything that is going to give one heart failure between the controlled lab tests and the empirical results. Agreed a single empirical test might be questionable. OTOH, this comparison IMOP simply says : While the K&N filter did not perform as good as some of the others,it is good enough for this application based on the empirical data presented.---Keoke