1977 400F2 first restore project

[smoothoperator]

I've taken off the rocker cover so first look inside the engine. Just 3 pics so far I'll add some more to the album later. Feel free to comment!

https://photos.app.goo.gl/bHPeUnzFJK92wHHp7

[Nurse Julie]

I wonder what has caused that damage on the end of the cam 🤔 It almost looks like the mice have had a nibble 😬

[smoothoperator]

I was a bit apprehensive of how it might go getting the head bolts undone however in the end I got lucky and it wasn't an issue. One of the nuts in the spark plug recess was actually not tightened. Once I had all the nuts off I could see that the rear stud on number 1 has been replaced, I have taken a photo of it. Taken the sump off and found it to have a radial crack near the drain plug, so a replacement sump is needed. I've taken some pics of the top end with the cam out to show the journals, I think they look OK. Next job is to remove the head, so any tips on that would be welcomed. By the way the end of the cam looks fine I think the mouse marks are a trick of the light.

https://photos.app.goo.gl/bHPeUnzFJK92wHHp7

[McCabe-Thiele (Ted)]

Good progress mate I wish I could have gotten further with my strip down  before my operation intervened.

I've been advised not to even drive my car until around the 3rd January next year.
 
I will follow your strip down with interest until I can return to my project in March 2021 shame about the sump issue.

Did you manage to do a Hot compression test ? The head looks reasonable how do the piston tops look?

[mike the bike]

You can always get the cracks in the sump welded.

[smoothoperator]

I need to give the sump a good clean before I can see how bad the crack is and whether to replace or weld. Meanwhile I have the barrels off so the internals are starting to reveal themselves. I've added some more images. I think the pistons are original, they are Honda, and a quick measurement of the bores with my £10 calipers gives a measurement of 50.8mm both top and bottom of all 4 bores. The rings on the pistons are moving freely although I've only had a quick look so far. The bores are in good condition on all 4. Now I need to get the garage organised before taking anything else apart as it's becoming difficult to find anywhere to place my feet!

https://photos.app.goo.gl/bHPeUnzFJK92wHHp7

[Bryanj]

Been a bit of blowby but a very light hone and new rings should cure that, plus a good clean of course

[smoothoperator]

Thanks for that Bryan it's very reassuring to have an expert opinion.

[McCabe-Thiele (Ted)]

I have to say the pistons look pretty good - what was the mileage out of interest ?
As Bryanj has said some blow by - looking at the cylinder head it's been a tad rich that might aggravate the blow by as excess fuel washes down the side or be a reflection of short journeys with choke use ?
Back in the 1960's when I was stripping down my Mini engine every 3 or four months I was always miffed to find the carbon deposits I had carefully removed each time spring back even with quality unleaded fuel.
I eventually started to blame the fuel so started using only one brand of petrol - it was "I.C.I." fuel it was a synthetic by-product from town gas coking plants & the chemical industry. It had a greater specific gravity than any other fuel due to a higher proportion of branched hydrocarbons it was said at the time.
When I moved to Bradford being a poor student I bought the cheapest 5 star that was available "NAFTA" I think it was Russian  - after 3 months I had to do a decoke as the cylinder head was so badly gummed up!

Not thought about it before I wonder if the Hondas are okay with unleaded petrol ?

I hope mine is that good when I get it stripped down.

[Bryanj]

 Hondas were designed from the start for unleaded as thats what the yanks wanted and it was the biggest market

[smoothoperator]

I've cleaned the sump and removed the baffle plate which was a pig to unscrew. I have checked for leaks and it holds water so regardless of the crack I can't see that it would have leaked oil. Applying finger pressure on the area around the crack doesn't create any visible movement of the crack. Tapping with a spanner doesn't give any changes in tone around the sump side. One image shows the crack as seen from the outside of the sump. Another shows 2 very small cracks on the inside, next to the sump plug. The 3rd image shows the inevitable "present" I found in the sump once I removed the baffle plate. I'm tempted to refit this sump as is, would this be dumb?

https://photos.app.goo.gl/8CbsUnvx6BwhmYKLA

[taysidedragon]

You won't know for sure if it leaks until it  gets hot and contains hot oil.
Add the engine vibration as well and you'll soon know.

I'd get the outside crack welded or get another sump pan.
The spring looks like a cam chain tensioner rod spring.

[Bryanj]

Oil will wich through the crack and cause a mess where water wont drip through

[smoothoperator]

Thanks for the advice guys I'll look for a replacement. No rush as I'm now taking the engine apart to find out what else might be knackered. Got the engine out today, front left lower engine mount is sheared, it was "glued" in. Feels like the work really starts here.

https://photos.app.goo.gl/bZUXdfnkSrRnsyKRA

[smoothoperator]

Thanks for the advice guys I'll look for a replacement. No rush as I'm now taking the engine apart to find out what else might be knackered. Got the engine out today, front left lower engine mounting bolt was sheared, it was "glued" in. The remaining bolt is I suspect going to be difficult to fish out. Feels like the work really starts here.

https://photos.app.goo.gl/bZUXdfnkSrRnsyKRA