Thread: TD5 blow-by remains

Originally Posted by Graeme

That bearing was woeful - I wondered if the caps had been mixed-up or fitted the wrong way round.

I was thinking the same thing(woeful) and after only 5600km!!!!!


I think the TD5 caps are made in such a way that they can't be used with the wrong rods (or if they are they won't fit anywhere near properly and will be damaged)

I keep wondering if these guys really know what they are doing. I don't think the TD5 is an engine where you can get away with much "that's close enough" attitude. (IMO)

I agree the oil pressure should be checked ASAP

I'm keen to hear how this all goes and what the culprit is/was


Fraser

Originally Posted by fraser130

I think the TD5 caps are made in such a way that they can't be used with the wrong rods (or if they are they won't fit anywhere near properly and will be damaged)

Yep, if a big-end bolt is done-up with the cap the wrong way round, or the wrong cap, then replace the conrod, due to the fracture joints requiring a perfact match.

Originally Posted by discowhite

thanks, the ac was on and the clutch fan also kicked in

cheers phil

JC

Blowby to me means quite a blue haze coming from either the oil filler cap or the dipstick tube.
In both instances with the main breather pipe from the rocker cover blanked off.
Or simply from the disconnected rocker cover breather pipe.
That one only seemed to be a natural pulse, no real oily fumes.

Any 5cyl. engine is going to have unequal pulses from the crankcase, and even at 0.5% blowby is going to build some additional crankase pressure.
Taper face, low radial pressure rings are designed to minimise bore wear, but a side effect is to allow an increase in bypass of combustion gasses.

Probably the reason for todays high detergent dispersal oils.
I ran a S1 L/R (2l petrol) for 230000 "miles" on Mobil delvac oil, the last time I had the head off before I sold her the chrome plating on the cyl. walls was still evident. But she always had a whisp of blowby and used up to 3 pints/1000 miles pretty much from new.

But they were not built as a "throw away" engine. ie cant bore, cant grind the crank, cant replace cam bearings etc.

Sold the old girl to a restorer in Canberra, hope she is still going well.
llandro

Sorry for the quiet period.

Oil pressure tests were done and all checked out above spec.

Phil my video was done when the motor and coolant was around 55'C so none of my electric fans were running, just the engine. I have two fans on the radiator, one at 86'c and another at 98'C.

This was done as I ran head temps of 92'C and coolant temps of 96'C when travelling on a good day.

I've now done 386km's. Just came back from an easy and slow sand drive. Hitting the tar, I took her up to 120km/h and she started to heat up. Slowed down and managed to keep the head temp at 110'C and coolent temp at 115'C with the heaters ON !

Got home and found the thermostat stuffed. It is closed... The coolent temp I'm reading is misleading when there is little water flow as it is situated too close to the head itself. At 115'C I only had my first fan running so the radiator was not at 96'c yet.... I'll have to redesign that one.

As I thought this rebuild was starting to show promise... now a bloody heat issue again.

OR - is this related or symptomatic ?

There is no water loss and the oil so far looks spankingly clean and new !!

I also noticed when driving slowly back ( 80km/h), that my fuel consumption was really high - that needle was dropping fast.

I'm at a complete loss, so I'm just trying to give info here. Gut feel still tells me there is something wrong with the head ?

Thanks once again for all the responses.

Ok, so I've been reading a bit.

I replaced the thermostat with zero difference ! While bleeding the system I noticed the following - With the thermostat closed and the expansion tank open, I get water flow at the bleeder plug. When I close the expansion tank the water flow at the bleeder plug slows to a dribble.

If I close up everything and take it for a drive, the water (front engine temp) goes up to 105'C while the back of the head is still at 70'C. The water pipes definitely pressurise. Back should be warmer than the front, surely ?

I've noticed small constant bubbles in the expansion tank - to me this shows combustion gasses.

Cracked head / gasket or injector blow by.

Your thoughts - I'm going to do this job now. The only way to get a job done right is to do it yourself !!

front to rear of the motor should show simillar temps.
bubbles arnt a good sign, try vacume filling the system with coolant. this is the only way ive found thats fool proof.
also there are simple testers that can tell you if there are combustion gasses pressant in the headder tank.

leak tester
GDCT16, Tester, Combustion Leak

vacume filler
RADKITPLUSJR, Refiller, Cooling System, Vacuum

cheers phil

Thanks Phil - just picked up those 2 kits will have some fun later tonight.

I solved my heating problem !!!! As mentioned I replaced the thermostat but didn't check the pipes. I just merely transferred all the piping from old thermostat to the new one. Yip the damn thing is wrong way round. "PUMP" doesn't go to pump !!! My mistake for not checking up on there work done !!

Now how's that for TD5 durability, over 6000k's like that before the thermostat went...