richURVAN Posted December 18, 2021 Report Share Posted December 18, 2021 Hey folks I just picked up this Van and I've been checking it over the past few days . . . It has an overheating issue which I'm in the process of diagnosing / repairing already with the help of this forum. There are some other things I've noticed on the engine that don't look quite right, here's some pics below; Vaccum Chamber on side of dizzy doesn't have a wire connection? Elec wire to dizzy frayed, and I traced that hard pipe back across the engine to a rubber hose which is just cut? Elec wire to temp gauge probe on top of thermostat housing is a bit frayed? Occasionally both the temp gauge and fuel gauge will completely drop out not sure if this is the cause. Some sort of heat transfer case/pipe on top of the exhaust manifold to a hole in the side of the engine bay, can't see it would do an awful lot? Two holes on inlet hose to airbox both plugged up? I'm just guessing but should one of them be the be for crankcase oil breather hose and then maybe the smaller hole is for an air sensor of some sort? Could this be the crankcase oil breather hose that's been cut and plugged up? Pic taken from bottom of engine on the inlet side. Hopefully most of these are 'improvements' done by the previous owners! Appreciate any advice. Ta, Rich Quote Link to comment
datzenmike Posted December 18, 2021 Report Share Posted December 18, 2021 First is this an EFI engine or carburetor? Does the air filter have one (carburetor) or two (electro-injection) butterflies holding it on??? I see you have a 4 wire distributor, so is it points or electronic? More important is the vacuum advance does not appear to be hooked up. Should connect to a metal tube going over to the intake side. Is this the wire that was on the distributor?? That is the ground for it. Get one of these... Do same with the temperature sender. Keep in mind that there are 2 temperature senders/sensors on an EFI engine and only one on a carburetor engine. Warmed air from the hot exhaust is usually mixed with cooler outside air as part of the ATV (airt temperature control) system and used mostly on carburetor engines and why I asked if this was an EFI engine. Is it??? Can't tell where this is, got picture from farther back?? Quote Link to comment
richURVAN Posted December 19, 2021 Author Report Share Posted December 19, 2021 Hey Mike, Thanks again buddy! It's def carby. Can I also assume it has points ignition then? If not I'll double check tomo when I'm back with the Van. Will also take a few clearer pics of the underside and that plugged up hose. Quote Link to comment
thisismatt Posted December 19, 2021 Report Share Posted December 19, 2021 Adding some heatshrink tubing (adhesive lined preferred) will act somewhat as a strain relief to help support those wires. Quote Link to comment
KELMO Posted December 19, 2021 Report Share Posted December 19, 2021 That one that Mike wanted a farther back pic looks like a water connector but also looks to be coming out of the block. So it could also be crank vent. If this is a GC22 van, I would think Z24 but in 1991? Probably not. Can we get what type of motor this ride has? Quote Link to comment
richURVAN Posted December 20, 2021 Author Report Share Posted December 20, 2021 12 hours ago, KELMO said: That one that Mike wanted a farther back pic looks like a water connector but also looks to be coming out of the block. So it could also be crank vent. If this is a GC22 van, I would think Z24 but in 1991? Probably not. Can we get what type of motor this ride has? Yeah I looked a few times from bottom and top and couldn't suss exactly where it was coming from, somewhere below the inlet manifold . . . It's a 91 Nissan Urvan with the Z24 5 Sp Manual. I'll upload another pic further back for Mike. Quote Link to comment
richURVAN Posted December 20, 2021 Author Report Share Posted December 20, 2021 This is the best I could do . . . After another inspection I think it's coming out the bottom of the intake manifold (which the carb is bolted on top), and I traced one of the pipes to the front grille where I assume it goes up to the heater core, so must be a water valve/junction? Quote Link to comment
datzenmike Posted December 20, 2021 Report Share Posted December 20, 2021 My thoughts too. It's on the intake manifold bottom. The intake has coolant circulating out of the head along each runner and out that fitting and eventually down to the lower radiator hose where it enters back into the water pump. It should also have a hose going to the heater core. The block vent is on the opposite side behind the exhaust manifold and has a metal pipe running around behind the head to the PCV valve on the intake. Quote Link to comment
richURVAN Posted December 21, 2021 Author Report Share Posted December 21, 2021 18 hours ago, datzenmike said: My thoughts too. It's on the intake manifold bottom. The intake has coolant circulating out of the head along each runner and out that fitting and eventually down to the lower radiator hose where it enters back into the water pump. It should also have a hose going to the heater core. The block vent is on the opposite side behind the exhaust manifold and has a metal pipe running around behind the head to the PCV valve on the intake. Aha got ya, and yes there is one hose going back to the lower rad junction and one to the heater core. Where that third hose is meant to go who knows? Found the block vent on the other side as well, perhaps after the PCV there should be a hose returning to the air inlet hose to plug in that hole? Where exactly is the PCV on these any ideas? Quote Link to comment
datzenmike Posted December 21, 2021 Report Share Posted December 21, 2021 The PCV valve is mounted in the intake manifold on the valve cover side of the carburetor. Intake vacuum draws fumes out of the crankcase by a one way valve in the PCV valve. Air that replaces air drawn into the PCV valve is piped from the air filter to the valve cover by a rubber hose. It's a closed system. There's coolant in that plugged hose. I don't know where it goes. Can't find it on the N American Vanette (it was only around 3? years. Quote Link to comment
richURVAN Posted December 21, 2021 Author Report Share Posted December 21, 2021 1 hour ago, datzenmike said: The PCV valve is mounted in the intake manifold on the valve cover side of the carburetor. Intake vacuum draws fumes out of the crankcase by a one way valve in the PCV valve. Air that replaces air drawn into the PCV valve is piped from the air filter to the valve cover by a rubber hose. It's a closed system. There's coolant in that plugged hose. I don't know where it goes. Can't find it on the N American Vanette (it was only around 3? years. I would of thought the Vanette & Urvan would be similar. I can only guess that it was a coolant feed to either the EGR valve or IACV which has been bypassed or removed 🤷♂️ Quote Link to comment
datzenmike Posted December 21, 2021 Report Share Posted December 21, 2021 The vacuum advance and the EGR are ported vacuum sources on the carburetor. Both feed through a T V V (thermal vacuum valve) that when cold leaks air from the air filter into the hoses and destroys the vacuum. When the coolant warms up the T V V closes the leak and vacuum is sent to the vacuum advance and to the EGR thus these can only work when the engine is warm. The T V V is on the intake manifold and screws into the water jacket there. Quote Link to comment
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