Big ends

[Spider2]

Investigating a rumble when hot and under load. Wrestled the sump off. # 1 big end bearing shells were in 3 bits not two! And minus the tangs. I will try and post a picture.

[Spider2]

Ho do I post a picture?

[LCR1967]

What is the condition of the crankshaft. The journal bearing appear to be heat stained, indicating insufficient lubrication pressure through the crankshaft main journal. Is the crankshaft journal ports free on debris?

[Spider2]

Hi,
Yes I agree with you it looks like a lack of lubrication. I am going to do several plasti gauge checks with good shells in and check #1 main bearing. It that is good then I guess the passage way is blocked to # 1 big end. What is a good way of cleaning out this passage way, bearing in mind the engine is in situ

[Spider2]

And surprisingly I can feel no ridges on the journal when I run my thumb nail across it.

[LCR1967]

Hi,
Yes I agree with you it looks like a lack of lubrication. I am going to do several plasti gauge checks with good shells in and check #1 main bearing. It that is good then I guess the passage way is blocked to # 1 big end. What is a good way of cleaning out this passage way, bearing in mind the engine is in situ

There are several bungs in the counterweight that are removed and flushed to ensure all internal passages to the feeder holes are clear from debris, oil build up or any sludge. I cannot think of a good way of thoroughly cleaning the passages with the crank still in situ. The only option would be to use a suitably sized pipe cleaner to clean each of the journals passages that feed the ends.

[lancianut666]

Take the engine out, surely the crank needs a complete clean out and all the bearings need replacement. With an engine crane it is an afternoon of spannerwork.
Clarkey

[davidwheeler]

I have always found it easier to lift the car off the engine/subframe but chaqun a son gout.

[Spider2]

Firstly, thanks to everyone for their sound advice and support. However, a lot of you are not going to be happy with what I have done.
I have replaced #1 big end shell and I am going to re-inspect after 250 miles. If it shows any signs of distress I will do a bottom end overhaul. I have to say that the engine now sounds so much sweeter. It idles smoother with no bottom end rattle on start up. The advantage of this scheme is that I need the car driveable as it it goes away for a small amount of bodywork next week. It also gives me time to contemplate and plan a possible bottom end overhaul in the spring. By the way, the plastigauge reading was 1.5 thou. Not bad!
To that end, for little money, I have bought a core engine. This autumn/winter I will disassemble it and assess whether or not it is overhaulable. Either way I will have fun doing it and it will give me the confidence in doing the possible bottom end on my engine. As a retiree I have plenty of time on my hands so I can be slow and methodical.
To tap on the wealth of knowledge here, I am starting a new thread called "my engine overhaul". I beg your forgiveness in advance for the numerous and obviously stupid questions I will be asking.