Getting back on the road

Weird thing is the sound is coming from the top I think. I pulled the valve cover and ran the engine for a brief moment. Messy sure, but no noise from the camshaft. Only other thought is the auxiliary drive bearings. I just need to pull the sump and check there next. Just not in the mood to lay under the car at the moment.
 
Good news on the noise front! Dropped the sump and found the foot of the lower timing chain tensioner had fallen off! Fortunately I had only run the engine a little after the noise started because of the carb issue so on a little aluminium dust in the oil (I'll be replacing it anyways) so I think no worse damage. New tensioner already ordered from Amazon (would you believe they have the Rolon ones in stock?). If joe comes through with a replacement float this week I should make the rally!
 

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Well, just got off the phone with Joe Curto. Turns out I have the early style floats with the floppy arms. So my theory is that as the carbs warm up with the engine running the plastic arms were softening and the float twisting instead of shutting the valve properly. Anyways, I've ordered a pair of the later, stiffer designs (left and right handed) from him and should get those tomorrow. I'll let you know if that works ok.
 
I was going to suggest to try the tensioner because i had a similar incident a couple of years ago with the upper one, but you found out soon enough.

Thankfully, there were no further problems.
 

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Yes, I've read since that this isn't unheard of on the new tensioners. Amazon are being a little slow shipping the part (I guess its something they have to source too?). So if it turns out that they don't get it shipped before Wednesday I will use one off my spare engine. I am guessing that one is an older product that's going to be reliable.

So, fingers crossed, Beryl will go to the ball (make that rally) on Sunday!
 
Got the tensioner switched over last night. The old one (well 1500 miles in my book isn't old.... grumble grumble) had very cleanly delaminated the rubber foot from the shaft. The small boss on the back came off during removal, what a piece of crap! The new one dosen't look much better, but Rolon seems to be the only available brand for the tensioners. Unless you know of another that I can get?

In the future I know to use a ratchet with a pivoting handle to get the correct angle on the mounting bolts. And to stick the tab washer on the plug with some grease, and hold the plug bolt with some grease on the side of a screwdriver blade while tightening with a 7/16" spanner. That should save me a good hour of swearing!

I did look at the tensioner on the old engine I pulled to see if was a different brand. But true to all the other work performed on it by the nameless mechanic of doom the plug bolt was missing. The engine had been running with just the spring force holding the chain in tension! I was right to not trust that engine it seems!

Here's a pic of the old one.


The new style floats arrived yesterday too. It felt like Christmas coming home from work! Timing chain tensioners, SU floats and a 5 quart can of Lucas Classic 20/50 oil!

I swapped those over with the old ones, talk a bout a difference in stiffness! The old ones were so floppy even when at room temperature, heavens knows how floppy they are when in a hot engine bay! I'll fit the carbs after refitting the sump this evening with luck. Also with luck this will help cure the venting of fuel from the front carb. Only thought I have after that is some sort of vibration issue causing it, but why only the front carb if that's so?
 

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Steve

I've just had a timing chain kit delivered and the tensioners are made by Rolon, as is the top chain. Bottom chain is a Rover part.







I'll be doing this job the week after next, along with a few others. I've not been able to have a look at the bottom tensioner on my car but the bottom chain is very noisy. My engine still has its original tensioners. The noise might just be down to low oil pressure (no gauge on my car) so I'll be changing the bottom end bearings too. If the tensioners look okay I'll leave them and keep these as spares.

Dave
 
Hi Dave, I would check how well the rubber is bonded on the new tensioners. Rollin was the brand I used too. Hopefully you have NOS. Ome thing was the boxes the tensioners came in were labeled Made in India.
 
Fixed the flooding carbs today. Turns out there were small burrs on the float valve needle flats. I found a guy on a mini forum with the exact same problem of flooding when hot. He'd found the burrs and filed them off. I used some 400 grit wet and dry. And it seems to have worked. I have about 20 miles under her belt now. I did have one stop at a traffic light where she felt like she was running rich but a quick flutter of the accelerator seemed to fix that. Fingers crossed for tomorrow's rally!
 
Well, it seems I hadn't cured the problem. Aw my post on the lounge about what happened instead. viewtopic.php?f=22&t=21230

Joe Curto has sent me some new upgraded valves, free of charge to try out. So I'll have a go with those as soon as I have some time to fit them. I managed to pull the carbs again this morning (new record, both carbs off in under 25 minutes included getting the tools out!). So maybe tonight if work, time and traffic allow.

The new valves are viton tipped, but have spring loaded plungers on their base like the older style brass valves and a small wire loop that hooks over the tab on the float. I did notice that the brass is of a much higher finish, the valve needles have been tumbled so there's no sharp edges to catch. Fingers crossed this'll fix the problem once and for all.
 

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Fitted the Rolls Royce style needle vales today. Much better, no flooding with the floats level with the carb body. Although it does feel a little lean when tuned as per instructions. I might whip the carbs off tomorrow and set the floats at the correct level of 1.00mm below the carb body. The weather here has been more reasonable at around 84°f instead of 95°f we've had recently. I can't help think that the higher temperatures haven't helped with things as petrol changes density and viscosity dramatically with temperature. I've also ordered some self adhesive heat insulation to put on both sides of the heat shield as per Pilkie's suggestion. Just in case it's the temperature causing issues.

I also finally got around to fitting V1.2 of my throttle adaptor. This gives me full travel on the accellerator pedal and makes things a lot more comtrollable. I'll produce drawings and post them soon. If anybody wants 3D CAD to machine their own parts I can email that to, just PM me.
 
Had to pull the carbs again today. I found that having the floats flush with the base of carb body made for a slightly rough idle and what felt like a lean mixture when driving. I'be set them at 1.00mm between the float and the body as per SU instructions and refitted, warmed up and tuned them. Went for a 10 mile shake down and I finally have a running car. The new needles seem to be holding back the flow and she's idling nice and smoothly now. Power feels better and with the smoother throttle control she feels so much nicer to drive.
 
Thanks, I've come to the conclusion that HIF's are far more temperature sensitive than the old HS8's. And the float level can make a huge difference. I'd seen a lot of people setting theirs to flush with the base of the body and my car ran pretty poorly that way.
 
Would you believe it? Start the car today, and fuel is pouring out the front carb AGAIN! Arggghhh!!!!!

I pull the front carb and the brand new float is half full of fuel. I've put the old one back in and all appears good again. This is a new float produced by a company beginning with B. I'm so sick of HIF's now.

All running fine, felt a flat spot when I test drove her and remembered I had forgotten to reconnect the vacuum line to the dissy. Pulled over and the damn right angled rubber fitting had fallen off the vacuum line.
 
It is true that one of our biggest problems these days as classic car owners is the unacceptable low quality of the replacement parts.
I try not to throw away the parts that i replace, because i am not sure if the "new" replacement part will live up to my expectations.
 
Demetris said:
It is true that one of our biggest problems these days as classic car owners is the unacceptable low quality of the replacement parts.
I try not to throw away the parts that i replace, because i am not sure if the "new" replacement part will live up to my expectations.
Click to expand...

For that reason alone I have kept the timing chain tensioners I removed from Lady C's engine last week. They looked in good condition so just in case the new ones fail prematurely......

Dave
 
You're too right Dave. I had one fail in only 1500 miles of use. Of course it had to be the bottom one.
 
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