I give up! - advice on who can help - oil everywhere post rebuild

Guys, just took the van for a short test drive and it seems to be running very hot. After idling for 15 mins or so to check for oil leaks etc i went out and after maybe 3 miles i was up to 220. Stopped and waited a bit and came back and it was showing 240 ish. Cant quite get whats happening, sounds ok and drives ok. The engine does seem hot too. The gauge from memory never got to 220 that often so something is amiss i assume.... any thoughts? Belt seems to be good on tension by the way.

 

What’s your gauge measuring?

 

You have new rings and cylinders? It will get hot from friction. Do not just let it tickover!

 

If it’s measuring oil temp in Fahrenheit, they’re not too bad for a new tight engine (110 - 115C).

<edit> and as Zed says, don’t let it idle for long periods.

 

Just found a bit of the foam seal had come away and caught inside the fan. What a mare. Question is what i found it and has it all come out .

 

Used to only get to 220 on high speeds so def a worry. Gonna let it cool and hope none of the debris has blocked the oil cooler.

 

But that wasn’t with your new, tight B&Ps

Which oil cooler?

 

I used to run at 250F. But that was pressing on hard.

Check you havent jammed the thermostat rod, it might need a little tweaking to stop it catching on the heads with the flaps shut.. that took my engine up to 266F once. Then it cleared itself up just to annoy me.

But now you have put the seal in the fan, some fragments may now have worked their way into the fins of the heads.

Only small ones but it wont help.. i found a few bits of foam along with dead insects etc when I pulled my engine.

 

The oil cooler isnt in circuit at the mo, but yes that was with the new barrels.

 

They get very hot idling with new rings and barrels - there isn't much cooling oil being thrown around at idle speed - letting it sit and idle for 15 minutes is a very bad idea. Did you do that to the last one too?

 

Good. Keep it that way

 

Will be back on it tomorrow morn. Hopefully no damage done. The idling was limited with occasional throttle blips so not literally just ticking over at same revs by the way.
Wouldnt start properly after i pulled the stuff out the fan, but later realised in the rummaging i had managed to dislodge the switched live off the coil for the fuel pump relay so should have it going again tomorrow, another drive out and reset valve clearances. Hope all is well as have the tune monday. I will ask the guy to do the floats as i dont want to open a new can of worms...!
Good news on the footy eh!

 

All is well today, sorted the fuel pump connections and double checked the fan was clear. Went out for a spin to check temps and make sure all was well- ended up going quite a bit further than i first thought as all seemed good. Temp reached a max of a bit over 180 so it looks like the fan is clear. Its running smoother and better than i ever remember the old engine running. I guess before i just assumed that was how they were as had no comparisons to work with but its way more responsive, less hesitant on pull away and seems to have more pull on inclines. I just need to drop the oil now and check valve clearances ahead of the rawspeed tune up tomorrow afternoon. Happy days at last i hope.

 

By the way some time back I found this web site which has interesting stuff on piston fails-
https://www.memoparts.com/img/cms/Documents/Piston Failue.pdf

 

So... just back from Rawspeed in Plymouth. Graham is clearly a legend and clearly knows more from experience in 5 seconds by ear than can ever be learned from books. Anyhow after a once over and setting idle jets and some gas analysis he put it on the rolling road and did further checks and some adjustments. I think we went up a main jet size and after tweaks she made 54.9 BHP at the wheels which is apparently about 10-11 more at the engine. He thinks the engine is good as thats a pretty good reading for conservative timing which indicates good valves, barrel sealing etc and I guess as its a new engine and the rings bed this might improve a bit more too. All in all I think we are on the home straight.
We had one issue fuel related where when the engine bay is warm it looked like we were getting lines too hot and causing vapour lock type issues and miss firing which I need to sort. One other thing I noticed on the drive back in traffic was the electric fuel pump whirring at different pitches which seemed to be related to the supply to to the pump. I think what is happening is that on low revs the voltage at the pump which comes off a relay from the coil ign live is dropping and the pump drops pitch. Once revs go up the voltage goes up and the pump whirs faster- I would have thought the pump would run the same speed all the time??. I am wondering whether I can use a feed off the battery for the pump via the relay... does anyone know whether this is ok and what the wiring should be to do it as I say. I used the wiring in the pic enclosed.

 

I would take your fuel pump feed via a fuse (and relay) from the main +12V terminal on the starter, or from the battery, rather than loading the supply from the ignition coil.

Summut like below (use one of the two relay options, according to taste).

 

Snotty- I guess the diagram shown does away with the alternator shut off, but i dont think thats much to stress on do you? At the end of the day if u crash turn the ign off and the pump stops so ok...just dont crash.

 

It’s all a bit iffy, IMHO, even with the ignition triggered relay. You’re relying on the engine stopping in a crash, which may or may not happen. Same with something alt-triggered (I try to avoid loading up the alt light output). But…best to have something, I suppose. Best option would be an old-school crash switch like they used to fit in the boot of yer Sierra - a ball bearing and spring

As above, take the relay supply from the battery or starter post.

 

"Went up a main jet size" ... hmm.. so it was a bit lean maybe...

If you have a mechanical fuel pump and the engine keeps running, then this is the same as your solution in terms of safety so not a major issue..
There is another two relay solution with a fused feed off the battery positive for the fuel pump.

Without needing the ignition pulse triggered pulse stretching relay.

One normal relay coil fed from starter motor cranking feed the other from the alternator terminal. The NO contacts in parallel feed the fuel pump.

Or two diodes and one relay.. If you think fuel vapourisation is an issue you will forever be having to go and prime with the push button type solution. So automate it with the relay.

If your battery voltage is changing enough to change the note of the pump with engine speed., you need your battery and charging circuit looked at. It should pop up to about 14 volts almost immediately you come off idle.

More likely the pump runs faster because it has to move more fuel so the downstream pressure goes a bit lower, lets the pump spin faster.