running in my new 4.6 thor v8 drama

[deano2469]

hi all, well finally got the new engine in and plumbed. we filled fluids and gave it a start to run in cam. after 5 mins we had a lot of what looked like steam pushing out of bleeder valve , then top hose started leaking badly, lots of pressure, then reservoir started leaking steam, then fluid. we had a temp gauge and saw top hose was only 80 deg, radiator was in the 20-30 deg at bottom, yet when i took cap off after stopping engine water bubbled out everywhere and made boiling noises. i could not find a temp close to 100 anywhere with laser temp gauge. tried again two or three times with same results...what could i be possibly doing wrong, im really afraid im going to kill it. any help would be appreciated

[Pedro_The_Swift]

wow,, not good..
with the amount of money at stake now I'd buy a coolant vacumm pump,,

[DAMINK]

Damn man after 5 minutes i would not expect that.
Big air lock possible but unlikely. Thermostat failing possible.
Head gasket most likely.
Not the symptoms you want after a fresh rebuild! Not one bit!

Best of luck.

[bblaze]

air in system I reckon
cheers
blaze

[DAMINK]

Could even be a water pump i guess.

When you filled the coolant did you keep a gauge on the quantity? Not sure on your radiator size but normally you can calculate pretty accurately how much coolant is required.
Easy way to know if you have an air lock somewhere.

Also when ever i do a first start i never cap it up. Leave the cap off so i can see the water level but also so i can see when the thermostat opens, normally dropping the level and getting warm.
Then once topped up i will put the cap on.

If it was me i would be doing a comp test to satisfy my paranoia then if all good filling it with coolant again and giving it another go.

[deano2469]

cheers for info guys, DAMINK, mate iv'e got a mechanic coming tomorrow to fill,pressure test etc just to make sure no air and check hopefully for fumes to count out engine problem. might be best 120 bucks of whole ordeal. other than that it started and ran first go, the eas kicked in and worked perfect, and only engine fault prior to start up was the slow fuel pump but thats because relay was out on previous ignition on to fix eas. fingers crossed.[tonguewink]

[DoubleChevron]

I've had this on a lot of cars. These days I always crack the top radiator hose to see if the coolant will then gurgle through. The thermostat is most likely preventing you filling the cooling system. With one of my cars I always end up getting the motor upto running temperature... Then you shut it off ......................... and the coolant will then open the thermostat.... and suddenly the damn cooling system is empty. But you can now fill it and bleed it properly as the thermostat is open.

There is supposed to be a one way valve built into most thermostats... there is often a thermostat bypass path as well (this seems to get blocked ... usually by poeple cutting there own gaskets, gasket goo ..... or the fact people never check for it being block).

seeya,
Shane L.

[daf11e]

When mine was doing the same in 5 minutes it was the water pump...couldn't bleed it as it boiled so quickly. Do,you know the history of your pump?

[deano2469]

When mine was doing the same in 5 minutes it was the water pump...couldn't bleed it as it boiled so quickly. Do,you know the history of your pump?
i had the pump off original engine which was cleaned and checked and appeared to be like new. worst case might be that then, still waiting on mechanic to do his bit, next day or so. its definitely getting too hot prior to thermostat opening, which i checked on stove top and found it to be good.

Thanks for idea, its now on check list.

[daf11e]

Probably unlikely if it was checked......just a thought as it's exactly the symptoms mine had...
good luck!

[Keithy P38]

Unless you’ve bled a P38 cooling system before it can be quite daunting.

The engine needs to be at operating temp before you worry, otherwise the thermostat won’t open and you’ll end up with air locks.

1. Fill system
2. Start engine (coolant reservoir cap off)
3. After 30sec, hold engine revs at 2000, steady
4. Once thermostat begins to open (and if radiator is empty), you’ll need to begin topping up the coolant reservoir. Don’t let the level drop below the coolant reservoir and into the hose
5. Fluctuate revs from 1500 to 2500 sharply
6. Once mostly bled, the level in the reservoir will rise rapidly. When this level begins to rise rapidly, shut engine off, hopefully not spilling coolant out the top.
7. Let the engine cool for 10mins and repeat sequence 3 times. It’s important to fluctuate the revs sharply (and do it from the engine bay, not in the cab).
8. Once cool, top up reservoir if necessary, replace coolant cap and go for a drive and monitor everything.

No need to nose up or anything, I’ve always done it on flat ground.

Cheers
Keithy

[deano2469]

thanks guys for all ideas, we tried a few things and it was a combination. firstly, the radiator was 1/3 blocked. secondly and unknown to me at the time, the previous owner had put the bottom o-ring on the overflow cap in the center groove, thanks to MR Automotive for spotting this as i bought a new cap anyway. once both of these things were sorted, she lives. the next thing i found was the indicators on the left side were not working at all, no clicking even, yet the hazards worked all around. found plug into becm was only half pushed in, once seated al[thumbsupbig]l worked. only horn to get going now then rego. i did find a small white plug with white and blue wire to it with two black wires out near brake booster, its cut and i have no idea what its for, any ideas would be great.

again, thank you to all for assistance so far, cant wait to get it going.

Deano.

[DAMINK]

thanks guys for all ideas, we tried a few things and it was a combination. firstly, the radiator was 1/3 blocked. secondly and unknown to me at the time, the previous owner had put the bottom o-ring on the overflow cap in the center groove, thanks to MR Automotive for spotting this as i bought a new cap anyway. once both of these things were sorted, she lives. the next thing i found was the indicators on the left side were not working at all, no clicking even, yet the hazards worked all around. found plug into becm was only half pushed in, once seated al[thumbsupbig]l worked. only horn to get going now then rego. i did find a small white plug with white and blue wire to it with two black wires out near brake booster, its cut and i have no idea what its for, any ideas would be great.

again, thank you to all for assistance so far, cant wait to get it going.

Deano.


Glad to hear you found out what that was mate. Would have been a worrying time.

Not sure on this particular engine but my first thought regarding the plug was the stepper motor plug. Square plug with 4 wires around there.

[deano2469]

Gents, she runs ...pretty well now. i have the odd quirk still. with new radiator and cap, system now holds pressure...sure enough, the weak link was o rings at heater matrix turned to plastic and floor full of coolant...replaced and all good now after a carpet shampoo.I have a TC light on dash and abs failure..i found front sensor away from position by about 10 mm, thought that was problem...no, tested all sensors with multi meter...all the same as far as i can tell, still getting abs fault and tc light on...any idea? i was told a rear had failed so bought a new rear but both sides look the same on meter.. Now i bought a 2 inch lift kit second hand and have installed it all, rebuilt pump, rebuilt valve block. these new bags are not like the ones i m used to. mine originally have a removable collet so you can replace o rings which i went to do , only to find these new ones have a different inlet, with a collet i cant see a way of removing without squashing. i have a bad leak in a front bag through here. if anyone knows the secret to this please let me know.'its really hard to tell if the hose is seated and don't want to re use old bags if i can avoid it. Here are a few pics of high boy...doing brake pipes prior to any off road action, next week probably..

143867143868143869

[DAMINK]

Im loving the look of that car Deano.
Bars could do with a metal injection but beyond that im liking it a lot!!

[deano2469]

Im loving the look of that car Deano.
Bars could do with a metal injection but beyond that im liking it a lot!!Cheers DAMINK , I've got a front arb winch bar and winch to go on. It's off a discovery, got it with lift kit...gotta strengthen it up a bit for winch as has been modified a bit to fit p38.. will put up a post when on.

[zzsteve]

still getting abs fault and tc light on...any idea?

]
Have you read any Wabco codes with Nanocom or similar?
It maybe a 'brake switch failure' which can give ABS, TC fault lights. Need to fix switch and reset codes before they disappear.
HTH
Steve

[deano2469]

Thanks Steve, yeah I swapped a sensor that I was told had failed even though it looked OK, still the same, I've got car booked in for check up at MR automotive next week as I've got a knock sensor fail code now too and it's started pinking..I guess I will be spending. Cheers.
Have you read any Wabco codes with Nanocom or similar?
It maybe a 'brake switch failure' which can give ABS, TC fault lights. Need to fix switch and reset codes before they disappear.
HTH
Steve

[zzsteve]

Thanks Steve, yeah I swapped a sensor that I was told had failed even though it looked OK, still the same, I've got car booked in for check up at MR automotive next week as I've got a knock sensor fail code now too and it's started pinking..I guess I will be spending. Cheers.

OK, I just realised you have a Thor engine. I've been knock sensorless on one bank for over 3 years now and no codes come up on my GEMS. Replaced it, and no observable change...

[deano2469]

Oh, that's surprising. I will have to wait and see I guess, I want to cover off any wiring and sensor issues anyway, especially after rebuild. Thanks mate.

[prelude]

@zzsteve I have found the same on my gems. The knock sensor on the startermoter side had it's plug knocked off (due to exchanging the starter) and although I made a temporary fix that has long since failed and no errors have popped up for me either. I thought it weird but I guess the knock sensor is a NO circuit? ;)

Cheers
-P

[zzsteve]

Ha!
Same fault, same side. Mine had a mashed back-end of the sensor from a vigorous starter motor removal at some stage.
BTW, they are pretty close to 1 MOhm so, not quite open circuit. Must put a scope on the signal one day and see if it is visible.
Steve

[deano2469]

well guys MR Automotive found a few issues for me. The RHS knock sensor was melted, thanks to Pedro_the _Swift, the sensor was replaced and fault cleared. The LHS abs sensor shows a fault but sensor itself was changed and fault still comes up. I checked wiring and plug into computer module under glove box and got same signal as at sensor so i suspect that module might be no good. i think i have an exhaust leak but hard to tell with heat shields on and it might be how sensor melted...will check it out and keep you posted. car is running a lot better now and with new airbags in front, the pump failed. cant find fault with overheat or pressure , swapped a few bits around and got it working again but ordered a new one anyway..next trip will be around blend motors for HEVAC...got intermittent book, intermittent A/C and when i press screen clear button i only get air to drivers side..when i bought the car it had a little bag of pieces that had fallen off, screws, sunroof bits and a couple of white plastic gears...me thinks this is where to start..


cheers and a few more beers.

[Pedro_The_Swift]

Mario has the exhaust manifold sets cheap,,,, though mine was ( again!) the flange.... :wallbash:

[prelude]

Good work mate! can't wait till you can enjoy the finished product :)

I had what I thought was a leak in the exhaust manifold what turned out to just be a gasket. Might be lucky ;)

Cheers,
-P

[deano2469]

hey Pedro, i tried all the flange bolts and they seam fine..i did find a crack that has been welded in exhaust on the part that crosses over....i hear sommething still under hard acceleration on passenger side so will take heatshields off soon and have a squiz. Also eas pump stopped working. tried the heat sensor test..passed, tried the pressure sensor test...passed, still would not activate so bought a new pump from aerosus. bolted straight up and working fine now. pulled old one apart and swapped circuit ring off and played with carbon brushes, started working again...now i have a spare for my rescue kit. still working on abs module and drivers door latch to work as suspension rises with door shut and no interior light. work in progress.





Mario has the exhaust manifold sets cheap,,,, though mine was ( again!) the flange.... :wallbash:

[deano2469]

Baby got new shoes....https://uploads.tapatalk-cdn.com/20181015/83252673e63014ef43a9487a41ded202.jpg

[prelude]

They look good mate :) I would stick to highway mode though, keeps the gap between the tyre and wheel arches smaller, looks better :)

Cheers!
-P

[deano2469]

One of the gremlins since i got this car running had been the TC light on the dash and ABS FAULT coming up when started. today i bought a used abs module that lives behind the glovebox and installed. i had a fault come up from diagnostic at MR Automotive that said RHR sensor fail, but sensor was ok, they, and i, assumed a break in the wire at first. I traced wiring to this unit and got same readings at plug as i did at sensors so assumed, that should be in capitals, it might be this module. and it turned out to be, swapped plugs over to test and light on dash went out and no abs fault came up...HAPPY CAMPER.

Big thanks to clem for getting unit out for me this morning and the cup of coffee too.


Next!!!!



[bigsmile][bigsmile][bigsmile][bigsmile][bigsmile][bigsmile]

[deano2469]

Well guys, after 100kms, engine developed a knock and a sound that started like an exhaust leak. change the oil, swapped manifolds over as i suspected them as cracked...no changes. Took off a rocker cover (after removing inlet...thor...and replacing it after)..ran engine and the smoke and noise coming up through the heads where the pushrods go was insane...really loud exhuast leak noise to go with it....no oil or water loss, or water out exhaust...strange. took all plugs out, rear RHS plug fouled up badly, all else fine. bought a leak down tester and all cyls were 50-60% leak and could hear air escaping...not good. engine is out and back at builder as we speak so they can pull it down and have a look....anybody ever heard of such a thing? because all cyls down i fail to think it could be a head gasket,cracked piston,slipped liner, etc as would only be in one or two of the pots...again i assume but what do you think.

as usual i will keep you updated.

Deano

[Keithy P38]

Sounds to me like the heads were not torqued down.

Cheers
Keithy

[Pedro_The_Swift]

yep,, if all failed.

[deano2469]

Sounds to me like the heads were not torqued down.

Cheers
Keithy


yeah mate, could have been i guess..i took them(the builder) to be more reliable than that, i guess we will see.[bigsad][bigsad][bigsad][bigsad][bigsad][bigsad]

[deano2469]

Update as of a week ago. Engine apart at rebuilders, found gudgeon pin had moved enough to hit bore, that was knocking noise, would explain plug foul up and smoke. Looks like rings didn't bed in properly either. Block fixed, bore honed, just waiting on new rings, gaskets and reassemble. Replacing pins to a set I had previously in another engine...Looks to have been dodgy conrod, replacing pins as well as rod or rods.

[101RRS]

Now they are only a tight press fit with no circlips to hold them in place, they would have to move a bit to touch the cylinder wall. mu guess would be an initial assembly issue.

[Pedro_The_Swift]

how do you get a knock out of a moved gudgeon pin? out of a moving gudgeon pin maybe.... scraping the cylinder wall I can understand,, (but doubt a simple hone would fix afterwoods)
Hmmm,, how would a moved pin cause fouled plugs and smoke? lack of oil control in the cylinder would...

[Pedro_The_Swift]

I'm hoping thats another Thor you are getting your spares from,,, [bigwhistle]

[deano2469]

I'm hoping thats another Thor you are getting your spares from,,, [bigwhistle]


Hi Pedro, mate i gave them the rods from a gems 4.6, he was hoping to use one or all rods or pins to rebuild. is there a difference? i was not aware if that's the case.Also i was told the gudgeon had moved, i might have heard it wrong. the bore has been honed so it may have been pin moving in rod that made the noise. basically they will put back together once rods and pins are good. the piston moving around too much in bore was explanation for fouling plug..i took that as gospel, im no mechanic and it seamed valid. 101RRS , mate again i could have heard it wrong but yes press fit was the issue.

[deano2469]

Hi guys, well i picked up my engine two days ago and i am ready to start re-installation. The engine bores have been honed, a full used set of rods have been installed using the pins to reattach pistons to said rods. There was an issue with the pins that were part of the new oversized piston set were undersized. Enough for one of them to move. New ring set also installed as first set did not bed in properly. All new original parts were bought from Rimmer brothers in the UK. All cleaned and reassembled to long and ready to put back in car as soon as i can get motivated.

Ill keep ya posted on rebuild part 2, fingers crossed all good this time.

[prelude]

Good luck deano! Hope it's all smooth sailing from here on in ;)


Cheers,
-P

[Pedro_The_Swift]

The 4L Thor rods are longer then the 3.9 gems,, they did this to stop piston slap,,, can you run a complete gems piston/rod assembly in a thor block? overall length and diameter is the same,,
anyone?

[Mercguy]

The 4L Thor rods are longer then the 3.9 gems,, they did this to stop piston slap,,, can you run a complete gems piston/rod assembly in a thor block? overall length and diameter is the same,,
anyone?
The rod/stroke ratio affects several engine dynamics, including piston speed and acceleration, piston dwell at top dead center and bottom dead center, piston side loads, cylinder loading and bearing loads. These elements play roles in engine efficiency, combustion and wear.


Generally, a lower rod/stroke ratio means a higher rod angle (in relation to the crank and the gudgeon pin), which creates greater potential for accelerated wear to cylinder walls, pistons, rings and rod bearings. A low enough ratio, due to a more severe rod angle, can literally punch a piston right into the cylinder wall, out the block. You've no doubt seen images of rods being sent outside...


High rod/stroke length ratio engines, on the other hand, don't have the same friction concerns, but compromise in other areas. Air doesn't fill the intake with the same velocity (i.e. slower), but there is also less demand for the ports to flow as well since there is more time to fill and scavenge the cylinder. This creates periods of stagnant airflow at low revs and overall weaker torque figures.

In the case of the 4.6 the displacement increase offsets these issues to an extent, but it does not negate them entirely.

Without a significantly redesigned induction system and multivalve cylinder heads, altering the rod/stroke ratio isn't going to net you any huge performance benefit. There are many things to consider beyond just the 'will they fit'. cylinder pressures, dwell time, camshaft static timing and ignition advance all have a significant influence on the efficiency when changing the ratio.

Because of the stroke increase of the 4.6, the engineers opted for a 'safer' longer ratio to reduce the overall rod angle at the extremes of crank rotation. It also allows more clearance between the base of the liners and the rod.

There are always things to consider that are not entirely obvious, such as the piston acceleration and dwell time at TDC.

I've seen plenty of rover v8's stroked out to 5.2, but there is a fair bit of work involved in clearancing as well as high rpm stability.

[deano2469]

Gentlemen, engine in, all appearances are good. No noises no leaks. 300kms done so far ,only got to 250 last Time before exhaust noises started and knocking started at 500kms. Took out to rebuild at 1000ks...the countdown is on. 🤞🤞🤞🤞🤞[emoji482][emoji482]