newbee needs more help

[jkpace]

I have a 1972 TR6 that set up for a while. I have spent the last 3 years working on it off and on as money and time
allowed. I would like to thank the members of this form for all the help I have gotten from browsing the discursions
on problems the same as mine. I don't belive I would have gotten it running with out your help.
I have 2 problems I would like comments on.
1. After taking out the Transmission for the 3rd time trying to getting the clutch to act right. I have found that the bolts holding the drive shaft to transmission are loosening. I have experienced nothing unusual while driving to suggest the problem. The previous owner had replaced the factory bolt and nyloc nut with another type bolt,nut, and a lock washer. I've ordered the correct bolt and nyloc nut from TRW in hopes this is the cause. If anyone else has had this problem, I would like to here about.
2. I have one cylinder that burns a little oil and sometimes fowls the plug. The compression is good so I suspect a valve guide and don't want to replace the head just yet. I am considering putting in a hotter plug ( going from a 9 to a 12 )in that one cylinder. The plugs in there now are champion RN9YC. Am I asking for bigger problems than a fowled plug ?

Thanks again for all the help.

 

[crj7driver]

I just removed my driveline and it used nyloc type nuts and I never had any problems with it. Also you might throw a little red loctite on there for good measure. As for you plug issues, going hotter should not really hurt anything.
Cheap old champions are definitely the way to go.

My 6 used to foul the rear cylinder and one other fairly often. It did this for years and eventually got worse, but compression was good across the board. I needed to get it to pass emissions and running better so I turned it over to a very knowledgeable British car shop. Turns out that the way the distributor was indexed from the factory (where the points open in relation to where the rotor is pointing and the sparkplug wire is on the cap) was wrong from day one from the factory. Adjusting timing will help conceal the problem but not fix it.

What is involved is taking out the vacuum advance/retard and rotating the distributor to the correct position (so that the arm is pointing to spark plug wire when the points open) and then drilling a new hole in the distributor to hook back up the advance/retard mechanism while the distributor is in the correct position. It is really very easy, but explaining it is a little difficult.

Once they did this, with no other changes car passed emissions, ran like mad, didn't foul plugs and when warm would start with the shortest time you could engage the starter as possible.

To reiterate the British car shop said many of the cars came for Triumph with the distributor indexed wrong, so I would check this out. The car ran good beforehand, but amazing different with the change.

Good luck

 

[Alan_Myers]

[ QUOTE ]
1. After taking out the Transmission for the 3rd time trying to getting the clutch to act right. I have found that the bolts holding the drive shaft to transmission are loosening. I have experienced nothing unusual while driving to suggest the problem. The previous owner had replaced the factory bolt and nyloc nut with another type bolt,nut, and a lock washer. I've ordered the correct bolt and nyloc nut from TRW in hopes this is the cause. If anyone else has had this problem, I would like to here about.

[/ QUOTE ]

Hi,

Nylock nuts should never be reused, especially in a highly critical application like the driveshaft. If you ever see what happens when one comes loose at speed, you'll understand why it's "critical"!

I got quite a scare on my TR4 when I found old Nylocks on my TR4's driveshaft had loosened. 6 out of 8 bolts were only finger tight! The remaining two were all that was really holding, and they weren't particularly tight.

I replaced with the kit from TRF, which uses "jet nuts" instead of Nylocks. These are also self locking, but are all metal. They can be re-used a few times. I did find the bolts in the TRF kit slightly long for my taste, they ran awfully close to the diff housing in particular. So, I used flat washers under the bolt head to move them a little further away... I might have shortened them slightly, too. You could actually buy the same things locally, check at any local airport maintenance supply shop, or a good hardware store, to buy jet nuts and grade-8 3/8" NF bolts of the right overall length. The unthreaded shank section must be the right length, too, so that no threads are inside the hole where they would grind away at the hole.

I agree, even with "the best" fasteners, a bit of Locktite is a good idea. I've heard people say not to use the stuff on Nylocks, so I apply so that it's not on the white nylon part of the nuts, just the metal threads.

/ubbthreads/images/graemlins/cheers.gif

 

[Dave Russell]

[ QUOTE ]

2. I have one cylinder that burns a little oil and sometimes fouls the plug. The compression is good so I suspect a valve guide and don't want to replace the head just yet. I am considering putting in a hotter plug ( going from a 9 to a 12 )in that one cylinder. The plugs in there now are champion RN9YC. Am I asking for bigger problems than a fouled plug ?
Thanks again for all the help.

[/ QUOTE ]
Hi Jerry & welcome to the forum,
I believe that the original specified plug for your engine was the UN12Y. The modern equivalent would be the RN12YC, or what ever the present Champion number equivalent is. Your present RN9YC plugs are somewhat colder than the recommended RN12's. This would certainly contribute to plug fouling. I can see no reason to use the colder plugs unless the compression ratio has been raised noticeably. I would replace all of the plugs with the RN12YC or consider the NGK BPR5ES. You might be surprised at how much better it runs.
D

 

[Guest]

I never use Nyloc nuts anywhere on my car that I can help it. As Alan says, all-metal locking nuts are the way to go, and even then I rarely reuse these. Another name for them is Cleve Nut. They are cheap enough from a nut and bolt supplier, I usually keep packs of them in all sizes.
Loctite works well with these.

Bill

 

[Musicman]

I also use the NGK BPR5ES's. The car runs great with them.

I highly recommend them.

 

[Alan_Myers]

By the way, www.boltdepot.com is a good source of hardware bits, if you have any trouble finding things locally.

Cheers!

 

[startech47]

Alan's solution is great. Make sure you use grade 8 flat washers as well. You can find these at any good hardware or automotive store. If you use lower grade flat washers they could lower the overall grade rating of the fastener system over time.

What Alan says is correct. I had a clutch disc explode at 70 mph in an Austin Healy Sprite. I thought the transmission slipped out of gear, but when I tried to put it back in gear, the shift lever was vibrating so bad it knocked my hand into the passenger door. I was looking for a way out of the car, until I was able to stop on the shoulder. Thats when I found out how small a Sprite is. Replacing the everything from the flywheel to the rear end and repairing the transmission tunnel sheetmetal fixed the problem.

Good luck on your repairs, Phil

 

[Mark_Gibson]

I had a similar plug fouling episode on my TR-6, and it turned out to be oil rings. You can have good compression and still have bad oil rings; I know this, believe me! I at first thought guides also but once the motor was torn down, you could see where the plug fouling was coming from. I got away with hotter plugs for a bit (maybe 5000 miles), but eventually the plug fouling got to the point where I was running on 4 cylinders most of the time! Hey, but look on the bright side. The engine problem was what made me decide to do a frame off! Think of all the fun you're about to have.....(actually it was kinda fun, but also kinda expensive) Ha! Good luck,

 

[jerrybny]

Just like to point out that the NGK company web site lists the BPR6ES as being the correct sparkplug for the TR6. It says the BPR5ES is for the Spitfire. Just thought I would point this out. Don't know if it makes a difference or not but I perfer to go with what the part manufactor reccomends thats all. Also be aware that NGK.com is not the companys website. It is just a company that sells them. The official NGK company website is www.ngksparkplugs.com

 

[Andrew Mace]

I agree to a point, Jerry. But ultimately I prefer to go with the original Triumph recommendation, cross-referencing their specified plug to another brand as necessary. I seem to recall that different years of TR6 used different plugs, and the same was true with the Mk3 and later Spitfires with the 1296 or 1493cc engines. (Earlier 1147cc Spitfires used a totally different plug.)

 

[Musicman]

Jerry,

It's always okay to abide by the recommended plugs. According to TRF and other reputable outlets, both Champion's (regular and hotter version) and NGK's (regular and hotter version) plugs are all okay to use in the TR6. It really comes down to how your particular car performs with either/or plugs. With the regular Champions my car hesitated ever so slightly at higher revs (4,000 to 5,000 rpm). When I changed to the NGK BPR5ES's the hesitation vanished and the car performs wonderfully.