New engine running very hot

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boogiedude
Posts: 410
Joined: Mon Mar 02, 2009 5:22 am
Your car is a: 1978 spider 1800
Location: Honolulu, HI

New engine running very hot

Post by boogiedude »

So I've just completed my first engine swap/build. The specs are

1800 head and block
4mm dome pistons
single 38ADL carb
alquati 42/82 cams
miller adjustable cam wheels
lightened flywheel
marks aluminum radiator
stock electronic ignition
passenger mounted alternator

I just got it down off the stands and ran it around the block and it is HOT. My temp gauge isnt currently working( I think the sensors are faulty, need to swap with my senders in my old head once its cool) so I dont know what the temperature is but its to the point that the valve covers burned my hand and it's now starting to blister. This seems ridiculously hot and it reached these temperatures with the hood off the car, it would have probably gotten dramatically hotter if it was on.

I've filled the system and burped it, getting all the air out. The thermostat is opening(lower hose is hot). I dont really know where to start? Could this be caused by a lean condition in the engine? Something that struck me as odd is I had to advance the distributor farther than I used to advance it on my old engine to get it to start. My timing cover is off so I cant test it with a light, but I estimate it being 15+ degrees advanced.
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bradartigue
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Joined: Thu Sep 20, 2007 2:35 pm
Your car is a: 1970 Sport Spider
Location: Atlanta, GA

Re: New engine running very hot

Post by bradartigue »

If it is not your thermostat not opening or installed backwards then it sounds like your timing is waaaaay off. You can get the exhaust timing off so bad that the manifold glows bright red (I've done it). It also has the odd side effect of running quite well at idle.

Fix your temp gauges; then,
Check your thermostat, check the radiator hose temperature (are they hot?); then,
Recheck your cam positions, make sure the crank is at TDC on #1, make sure the distributor is firing on #4.
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bradartigue
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Joined: Thu Sep 20, 2007 2:35 pm
Your car is a: 1970 Sport Spider
Location: Atlanta, GA

Re: New engine running very hot

Post by bradartigue »

Well, I'm a dummy and didn't read your whole post.

Your crankshaft timing is at +15, which isn't a big deal, but I'll bet anything your camshafts aren't timed right. Get all that lined up: TDC, crankshaft at 0 degrees, cams at the pointers, distributor at #4 position. Do they line up perfectly?
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boogiedude
Posts: 410
Joined: Mon Mar 02, 2009 5:22 am
Your car is a: 1978 spider 1800
Location: Honolulu, HI

Re: New engine running very hot

Post by boogiedude »

I've got the gauge fixed now. Crappy splices had come loose. The problem with lining up the cams is that They're on adjustable wheels and the marks that were made on the inside of the cam housings to indicate proper timing have now washed off in the oil.... the castings on the cam housing are pointed directly into the center of the hole used for lining them up(if that makes any sense?) with the crank at TDC. Is there a way to determine proper cam timing with everything together and my marks now missing? I'd really rather not pull the head...
131
Posts: 672
Joined: Sun Nov 14, 2010 1:13 am
Your car is a: 1982 131 Superbrava warmed 2.0 litre.
Location: Tasmania, Australia

Re: New engine running very hot

Post by 131 »

Have you got the right camwheel on each cam? I've got a set of Jason Miller's adjustable cam gears on mine. When I fitted them, I had to compare them to a set of standard gears I have on a spare head. The hole in the gear for locating on the cam dowel is in a different position between inlet and exhaust. Having them around the wrong way can put your cam timing out by a considerable amount.
Mick.

'82 2litre 131, rally cams, IDFs & headers.
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bradartigue
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Joined: Thu Sep 20, 2007 2:35 pm
Your car is a: 1970 Sport Spider
Location: Atlanta, GA

Re: New engine running very hot

Post by bradartigue »

You'll need to know which is which (exh and intake) and be sure they are correct, then find out (from whoever made them) how to set them up initially. The cam box itself has a timing mark cast into it and (if you use stock wheels) it points at a hole in each. Barring anything else I'd slide on the old wheels and get the cams set to their stock position, then remove them and install your adjustables, mark them (with a punch!), and go from there.
So Cal Mark

Re: New engine running very hot

Post by So Cal Mark »

with adjustable wheels, you need a degree wheel or you're just guessing at cam timing
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boogiedude
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Joined: Mon Mar 02, 2009 5:22 am
Your car is a: 1978 spider 1800
Location: Honolulu, HI

Re: New engine running very hot

Post by boogiedude »

When the head was off, the cams were dialed in using degree wheels. The problem is, the match marks that were made have washed off into the oil in the cam housing. Is there a way to re dial them with head attached?
rlux4
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Joined: Thu Jan 10, 2008 8:32 pm
Your car is a: 1982 2000 Spider
Location: Granite Falls, Wa

Re: New engine running very hot

Post by rlux4 »

You could take off the cam covers and see what position the cams are in. But it would be easier to do it Brad's way and use your original pulleys to dial in positioning.
Ron
Ron Luxmore
rlux2n2@gmail.com
'82 2000 Spider: after 26 years between Spiders.
So Cal Mark

Re: New engine running very hot

Post by So Cal Mark »

when the cams are degreed, it's done based on their relationship to the crankshaft so it's impossible to do properly with the head off the engine
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boogiedude
Posts: 410
Joined: Mon Mar 02, 2009 5:22 am
Your car is a: 1978 spider 1800
Location: Honolulu, HI

Re: New engine running very hot

Post by boogiedude »

Refer to my 'how to cam timing' in GC V/W (Virtual workshop). TC cams must be set up with head off. The can be checked with the belt on, but not really setup on the engine without grave risk of bending a valve.
from guy croft on his forum, I was under the impression it could be set up just fine without the head on. They were set up using a dial indicator and degree wheels to determine when full lift occurred and then marked accordingly in on the rear cam bearing area
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manoa matt
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Joined: Thu Oct 26, 2006 4:28 pm
Your car is a: 1978 Fiat 124 Spider 1800
Location: Honolulu, Hawaii

Re: New engine running very hot

Post by manoa matt »

The head and cams were set up per GC procedure. (page 78 of original book) Once max lift was found the cams were dialed back/fourth and set for #4 to fire. Boogie should have found TDC for the block (and marked it accuratly?) and bolted the head on. Slip the belt on, give the engine 4 full rotations by hand and re-checked all the marks, then adjusted the cam pulleys.

Once the cams were dialed in the raised markes on the cam housings could be seen through the holes in the cam pulleys. One was pretty much right in the center, the other was a few deg off. However they should be within a few deg of optimum and the car should run.

Having the hood off while driving could reduce the flow through the rad, however with that big aluminum rad you should see a good running temp even with the extra HP at idle at the least.

You need some good diagnostics. Non contact laser thermometer to confirm the ACTUAL temps of the rad, and metal temp of the head. Put the timing cover back on and use the timing light to see where the initial and max advance are at.

Did you get a new crank pulley or are you using the stock 3 track pulley? With the dished H2O pump pully and the alt on the pass side the V belt will be on the last and smallest pulley. With that configuration, the water pump and alternator will be spinning faster than normal. Cavitation could be an issue with a fast spinning pump. Open impeller or closed??

With the money and labor involved with this new performance engine, or any engine build for that matter. Don't just pour in some oil and blast around the block. Check, double check, tripple check, dry build, and check and check again.
pastaroni34

Re: New engine running very hot

Post by pastaroni34 »

manoa matt wrote:Did you get a new crank pulley or are you using the stock 3 track pulley? With the dished H2O pump pully and the alt on the pass side the V belt will be on the last and smallest pulley. With that configuration, the water pump and alternator will be spinning faster than normal. Cavitation could be an issue with a fast spinning pump. Open impeller or closed??
If you're using the smaller diameter groove the alternator and water pump will run slower.. this will definitely contribute to higher temperatures at low rpm.

As for cam pulley installation, I have a guide here: http://www.millersmule.com/MillersMuleS ... tachment=4 That should get you 'rough' timed. Nothing will be spot-on without a dial indicator though.
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