Procedure for first time engine start

[v8alex]

Hopefully will be firing up the engine for the first time pretty soon. I have a 3.5L RV8 with a pretty standard setup - 220 degree duration Cam, HD timing chain, stage 1.5 heads.

In order to minimise screw ups, is there a standard procedure that should be followed or any critical checks prior to turning the key ?

I'm assuming the following actions are necessary:

1. Set crank to 4 deg BTDC
2. Prime oil pump with drill
3. Spark plug gap about 0.9mm
4. Check carb is primed with fuel

Also, some specific questions:

1. Is there anything special I need to do with the dizzy ? I have a Mallory electronic set up. I guess I need to get it set up such that the spark is ready for #1 cylinder

2. For the carb (Weber 500cfm), is there anything I need to do with the idle screws ? They have moved a bit since fitting - do I screw them in finger tight, then unscrew a certian number of turns ?

3. In terms of BTDC, I'm assuming this is on the compression / ignition stroke ! Is there an easy way to tell ?

Comments / guidance welcome !

Alex

[The Original Tom]

If you are priming the oil with a drill, (assuming you didn't pack the pump with vaseline?) then do it with the ign on and get someone to watch for the oil light to go out.
When you first crank it over, do it with the king-lead disconnected then it'll re-prime it, cover the bearing surfaces well, and give the bores a good wash before firing it. To check TDC on compression stroke, the only really easy way is to remove the rocker cover on the side with #1 cyl. Then rotate the engine until TDC and both the valves should be closed. If the exh. valve is closing and the intake opening just either side of TDC then you're on the exhaust stroke not the compression stroke.
I'd go for 6degs BTDC
With the fuel, you can only do a rough set up, and I've never used a weber so I don't know, but it certainly doesn't have to be accurate!

You need to let it run off load for about 20 mins at 2500rpm to bed the cam, but as the entire engine's spanking new (assuming main bearings etc?) and that requires a low revving environment immediately, I'd compromise for 2000rpm for 20 mins.

It's easy to be scared by all these worries with a first start-up, but as a guy from RPi said to me: "don't get hung up on the limits too much, how many people do you reckon bedded in their new SD1/Range Rovers when they first bought them? And how many of those engines are still driving that motor around after 25 years" I.E it helps, but the chances are the engine will still do 100k miles if you do cock it up slightly.

[kiwicar]

all good advice from Tom but dont "hold" it at 2000 or 2500 revs, vary it from not less than 1800 and not more than about 2800, change the revs slowly so as not to wash the bores with the accelerator pumps, in fact if you can reduce the stroke on the accelerator pumps so as to reduce this enrichment.
Keep an eye on it (I am sure you will) look out for sudden changes on the temp gauge, listen for air in the cooling system. obviously keep an eye on the oil pressure. if in doubt stop it, check it, restart it, don't sit it at idle while you investigate it.
have fun
Mike

[v8alex]

Thanks folks, this is very helpful.

Tom - when you say to give the bores a good wash - i take it this is squirt WD40 down the spark plug holes to lube the liner sidewalls.

Fingers crossed it'll go OK and I'll get her running.

The missus is away this weekend with little one, so the garage is mine all bank holiday weekend and my diet will be lager, hot dogs and engine oil !

Alex

[katanaman]

Tom - when you say to give the bores a good wash - i take it this is squirt WD40 down the spark plug holes to lube the liner sidewalls.

Alex

Oh god no don't do that! He means the bores will get splashed with oil off the crank. You should have built the engine with lots of oil on the bores anyway. so personally I would say spinning the engine without firing is unnecessary but I cant see it doing any harm.

[sidecar]

I think "kiwicar" means that the bores will be washed with unburnt fuel if you jab at the throttle due to the accelerator pump....this is not a good thing as the oil is removed from the bores and unburnt fuel ends up in the sump.

I found that the pilot screws on my weber were set far too lean to pick up well, mine are now set at 2.5 turns out, I run a typhoon cam which I think is 220 degrees. They were at 1+3/4 before I put stage III heads on so yours will be somewhere between those settings.

I run 8 to 10 degree static timing and 34 max but with fairly heavy bob weight springs because if the advance comes in too fast when running quite alot of static it will cause the engine to stumble. My motor idles much better with quite a lot of static timing. (9.75:1 comp)

When setting up the timing you need to find TDC with something better then a screw drivr down the plug hole! The best way is with a clock gauge on number one piston with the head off, you can then adjust the pointer on the damper wheel to point to its TDC mark. I'm not too sure how you can do this with the heads on as the plug hole is at too much of an angle for a guage to work.

Good luck, I'm sure everything will be near enough to get the motor running, its amazing what these RV8 lumps will tolerate!

Pete

[v8alex]

Thanks again - I did measure TDC with a dial gauge when building the engine with heads off and marked the crank pulley accordingly with a scribe, so I should get this bit pretty close.

Sorry I missed the point on bore wash - they were well coated with engine oil during the build.

Stage 1 should be to get the engine fired up - once this is done, I can play around with the distributor and idle screws to optimise the running. Promises to be fun.

Thanks again

Alex

[The Original Tom]

Sorry, I was a little vague! I mean get the oild flowing around and everywhere it should be. Regardless if whether you smothered the bores with oil when you built the engine, if it's sat for a while then a lot may have drained off. Hope it goes well!